collagen type XX trimer

description: A collagen homotrimer of alpha1(XX) chains.


GTPase complex

category: biolink:CellularComponent biolink:AnatomicalEntity biolink:PhysicalEssence biolink:OrganismalEntity biolink:SubjectOfInvestigation biolink:BiologicalEntity biolink:ThingWithTaxon biolink:NamedThing biolink:PhysicalEssenceOrOccurrent

description: A protein complex which is capable of GTPase activity.


name: classical-complement-pathway C3/C5 convertase complex

description: A heterodimeric protein complex that catalyzes the cleavage of complement components C3 and C5, and acts in the classical pathway of complement activation; consists of one monomer of C2a and one monomer of C4b; C2a is the catalytic subunit, but cannot catalyze cleavage alone.


starch utilization system complex

description: A bacterial cell envelope-associated multiprotein system, which binds and degrades starch.


name: methyl accepting chemotaxis protein complex

description: A transmembrane protein complex that consists of multiple methyl-accepting chemoreceptor protein subunits, a histidine kinase and a connector protein and which functions in the regulation of flagellar rotary motor activity in response to an external chemical stimulus.


name: transcription-coupled nucleotide-excision repair, DNA damage recognition complex

description: A protein complex that is capable of identifying lesions in DNA on the actively transcribed strand of the DNA duplex as well as a small subset of lesions not recognized by the general nucleotide-excision repair pathway. The wide range of substrate specificity suggests that the repair complex recognizes distortions in the DNA helix. It subsequently recruits a nucleotide-excision repair, preincision complex.


RNAi effector complex

description: Any protein complex that mediates the effects of small interfering RNAs on gene expression. Most known examples contain one or more members of the Argonaute family of proteins.


transcription factor TFIIIC1 complex

description: A transcription factor complex that forms part of the TFIIIC complex, observed in human. The complex is poorly characterized, but contains the 250-kDa form of HsBdp1, and is thought to include nuclear factor 1 (NF1). It stimulates binding by human TFIIIC2 and is required for transcription activity.


name: transforming growth factor beta activated kinase 1 complex

description: A protein complex that possesses protein kinase activity and activates the I-kappa B kinase complex (IKK) and mitogen-activated protein (MAP) kinases in response to TRAF6 signaling. It comprises the catalytic subunit TAK1 complexed to the regulatory subunits, termed TABs (TAK1-binding subunits).


name: nuclear proteasome regulatory particle, base subcomplex

description: The subunits of the regulatory particle that directly associate with the core complex of a proteasome located in the nucleus of a cell.


Vps55/Vps68 complex

description: A membrane-associated protein complex that is required for a late stage of endosomal transport. In budding yeast, this complex consists of Vps55p and Vps68p proteins.


DPS complex

description: A protein serine/threonine phosphatase complex that in S. pombe consists of the proteins Dis2, Ppn1, and Swd22.


Wnt signalosome

description: A multiprotein protein complex containing membrane-localized Wnt receptors and cytosolic protein complexes, which is capable of transmitting the Wnt signal. Contains at least a Wnt protein, LRP5 or LRP6, a member of the Frizzled (Fz) family, Axin and and a Dishevelled (DVL) protein.


PUMA-BCL-2 complex

description: A heterodimeric protein complex consisting of PUMA and BCL-2, members of the Bcl-2 family of anti- and proapoptotic regulators.


RISC-loading complex

description: A trimeric protein complex required for the formation of a mature RNA-induced silencing complex (RISC). In humans the complex is composed of the endonuclease Dicer (DICER1), TRBP (TARBP2) and the Argonaute protein Ago2 (EIF2C2/AGO2). Within the complex, Dicer and TRBP are required to process precursor miRNAs (pre-miRNAs) to mature miRNAs and then load them onto Ago2. Ago2 bound to the mature miRNA constitutes the minimal RISC and may subsequently dissociate from Dicer and TRBP. This complex has endoribonuclease activity.


Lsm-containing SMN-Sm protein complex

description: An SMN-Sm protein complex formed by the association of the methylated Sm proteins B/B', D3, E, F, and G, and Lsm10 and Lsm11, with the SMN complex. This complex forms Sm cores on U7 snRNA.


Bcl3-Bcl10 complex

description: A protein complex containing Bcl3 and Bcl10, which forms when Akt1 is activated by TNF-alpha to phosphorylate Bcl10; the Bcl3-Bcl10 complex is translocated to the nucleus.


DNA recombinase complex

description: A protein-DNA complex consisting of a higher-order oligomer of strand exchange proteins (recombinases) on single-stranded DNA.


name: PSI associated light-harvesting complex I, LHCIa subcomplex

description: A pigment protein complex that forms part of the photosystem I associated light-harvesting complex I; contains two proteins (usually about 24 and 21.5 kDa); has a fluorescence maximum between 680 and 690 nm.


laminin-522 complex

description: A laminin complex composed of alpha5, beta2 and gamma2 polypeptide chains.


DiaA complex

description: A homotetrameric protein complex consisting of a symmetrical pair of DiaA homodimers. Facilitates DnaA binding to the origin of replication during replication initiation.


trans-synaptic protein complex

description: A protein complex that spans the synaptic cleft and has parts in both the pre- and post-synaptic membranes.


exomer complex

description: A protein complex that forms a coat structure on vesicles involved in exocytosis of proteins from the trans-Golgi network to the cell surface; in Saccharomyces, the complex contains Chs5p, Chs6p, and Chs6p paralogues.


cobalamin transport complex

description: Protein complex facilitating ATP-dependent cobalamin (vitamin B12) transport through inner cell membrane (periplasm to cytoplasm) in Gram-negative bacteria. In E. coli the system is composed of a periplasmic cobalamin-binding protein (BtuF), an integral membrane homodimer, BtuC, and a cytoplasmic ATP-binding homodimer BtuD.


MAML3-RBP-Jkappa-ICN4 complex

description: A protein complex that consists of the intracellular domain of Notch4 (ICN4), the DNA-binding transcription factor RBP-Jkappa, and the transcriptional coactivator Mastermind-like-3 (MAML3); the complex is involved in transcriptional activation in response to Notch-mediated signaling.


description: An enzyme complex composed of 2-4 or more subunits, which usually contains nonheme iron and requires ATP for catalysis. Catalyzes the formation of 2'-deoxyribonucleoside diphosphate from ribonucleoside diphosphate, using either thioredoxin disulfide or glutaredoxin disulfide as an acceptor.


name: methyl-tetrahydromethanopterin:coenzyme M methyltransferase complex

description: A protein complex consisted of eight polypeptides. This complex catalyzes the formation of methyl-coenzyme M and H4MPT from N5-methyl-H4MPT and CoM during methanogenesis.


name: cytosolic aryl hydrocarbon receptor complex

description: An aryl hydrocarbon receptor complex found in the cytosol, in which the ligand-binding subunit AhR is not bound to ligand; consists of AhR, two molecules of HSP90, the protein kinase c-Src, and the immunophilin XAP2/AIP.


name: methionyl glutamyl tRNA synthetase complex

description: A complex consisting of methionyl- and glutamyl-tRNA synthetases. The tRNA synthetases present in the complex bind to their cognate tRNAs more efficiently than they do as monomers.


glutamate-tRNA ligase complex

description: An enzyme complex that catalyzes the ligation of glutamate and tRNA(Glu) to form glutamyl-tRNA(Glu).


radial spoke base

description: The short portion of the radial spoke that is directly anchored to the A microtubule of an axonemal microtubule doublet.


interleukin-4 receptor complex

description: A protein complex that binds interleukin-4 (IL-4) and consists of an alpha chain that binds IL-4 with high affinity and a gamma common chain that also forms part of the interleukin-2 receptor.


iron-sulfur cluster transfer complex

description: A protein complex capable of catalyzing the transfer of an iron-sulfur (Fe-S) cluster from one compound (donor) to another (acceptor), which may be a target protein or another Fe-S assembly complex. In humans, it consists of HSPA9, HSCB, GLRX5, ABCB7 and GFER.


photosystem I reaction center

description: A photochemical system containing P700, the chlorophyll a dimer that functions as a primary electron donor. Functioning as a light-dependent plastocyanin-ferredoxin oxidoreductase, it transfers electrons from plastocyanin to ferredoxin.


fatty-acyl-CoA synthase complex

description: A protein complex that possesses fatty-acyl-CoA synthase activity.


BORC complex

description: A protein complex that is involved in positioning of the lysosome within the cytoplasm and which is composed of BLOC1S1, BLOC1S2, BORCS5, BORCS6, BORCS7, BORCS8, KXD1 and SNAPIN. The BORC complex recruits ARL8 at the cytosolic face of lysosomes and couples them to microtubule plus-end-directed kinesin motors.


B800-850 antenna complex

description: Protein-pigment complex that absorbs light at 800 and 850 nm; is peripherally associated to the bacterial reaction center; transfers excitation energy to the B875 antenna complex.


exoribonuclease complex

description: A protein complex which is capable of exoribonuclease activity.


glycine-tRNA ligase complex

description: A multimeric enzyme complex which, in bacteria, is usually a tetramer of two alpha and two beta chains and in eukaryotes, is usually a homodimer. Functions in the ligation of glycine and tRNA(Gly) to form glycyl-tRNA(Gly).


7SK snRNP

description: A ribonucleoprotein complex that contains the 7SK snRNA. The 7SK snRNP plays a central role in RNA polymerase II elongation control by regulating the availability of active P-TEFb.


TRAMP complex

description: A multiprotein complex having distributive polyadenylation activity of a variety of RNA substrates including hypomodified and incorrectly folded tRNAs, pre-snRNAs, pre-snoRNAs, incorrectly spliced or processed pre-mRNAs, cryptic unstable transcripts (CUTs), pre-rRNAs and rRNA fragments released as part of rRNA processing. In S. cerevisiae, the complex consists of either Pap2 (also known as Trf4) or Trf5, Air1 or Air2, and Mtr4, and is involved in RNA 3'-end processing and in RNA surveillance and quality control.


fumarate reductase complex

description: A membrane-bound flavoenzyme complex consisting of four subunits, A, B, C, and D. A and B comprise the membrane-extrinsic catalytic domain and C (InterPro:IPR003510; InterPro:IPR004224) and D (InterPro:IPR003418) link the catalytic centers to the electron-transport chain. This family consists of the 13 kDa hydrophobic subunit D. This component may be required to anchor the catalytic components of the fumarate reductase complex to the cytoplasmic membrane. Fumarate reductase couples the reduction of fumarate to succinate to the oxidation of quinol to quinone, in a reaction opposite to that catalyzed by the related complex II of the respiratory chain (succinate dehydrogenase-(ubiquinone)).


Pip2-Oaf1 complex

description: A heterodimeric complex consisting of Zn(2)Cys(6) containing transcription factors Pip2 and Oaf1. It binds to the oleate response element (ORE), found in the promoters of fatty acid-inducible genes in Saccharomyces where, in the presence of oleate this bound complex activates the transcription of genes encoding peroxisomal proteins.


RasGAP-Fyn-Lyn-Yes complex

description: A protein complex that consists of a GTPase activator protein (GAP) for Ras and three Src family protein tyrosine kinases, Fyn, Lyn and Yes. The complex is involved in signaling upon platelet activation.


RISC complex

description: A ribonucleoprotein complex that contains members of the Argonaute family of proteins, small interfering RNAs (siRNAs) or microRNAs (miRNAs), and miRNA or siRNA-complementary mRNAs, in addition to a number of accessory factors. The RISC complex is involved in posttranscriptional repression of gene expression through downregulation of translation or induction of mRNA degradation.


description: A protein complex that consists of an alphaV-beta6 integrin complex bound to osteopontin.


GATOR1 complex

description: A GTPase-activating protein (GAP) complex that regulates TORC1 signaling by interacting with the Rag GTPase. In human, the GATOR1 complex consists of DEPDC5, NPRL2, and NPRL3. In S. cerevisiae, this complex is referred to as SEACIT and contains the Iml1p, Npr2p, and Npr3p proteins.


alpha-beta T cell receptor complex

description: A T cell receptor complex in which the TCR heterodimer comprises alpha and beta chains, associated with the CD3 complex; recognizes a complex consisting of an antigen-derived peptide bound to a class I or class II MHC protein.


E.F.G complex

description: A protein complex that comprises three core spliceosomal proteins, designated E, F, and G. Formation of the E.F.G complex is essential but not sufficient for the formation of a stable U1 snRNP complex.


nuclear pore linkers

description: A substructure of the nuclear pore complex (NPC) that serves to connect members of the central transport channel (composed of FG-nucleoporins) to the core scaffold (composed of the inner and outer NPC rings). In S. cerevisiae, the linkers are Nic96p and Nup82p. In vertebrates, they are Nup93 and Nup88. Components are arranged in 8-fold symmetrical 'spokes' around the central transport channel. Both linkers can be isolated in association with specific FG-nucleoporins, complexes that are sometimes referred to as the Nic96 complex (Nic96p-Nsp1p-Nup49p-Nup57p) and the Nup82 complex (Nup82p-Nup116p-Nup159p-Gle2p).


name: RNA polymerase I transcription regulator complex

description: A transcription factor complex that acts at a regulatory region of a gene transcribed by RNA polymerase I.


APC-IQGAP1-CLIP-170 complex

description: A protein complex that contains the tumor suppressor protein adenomatous polyposis coli (APC), the small GTPase Cdc42, and CLIP-170; may play a role in cytoskeleton organization and cell migration.


clathrin coat

description: A membrane coat found on coated pits and some coated vesicles; consists of polymerized clathrin triskelions, each comprising three clathrin heavy chains and three clathrin light chains, linked to the membrane via one of the AP adaptor complexes.


name: type IV site-specific deoxyribonuclease complex

description: A complex consisting of two proteins which acts as an endonuclease in DNA sequences containing a specific modified recognition site. Modifications may include methylation, hydroxymethylation, and glucosyl-hydroxymethylation.


collagen type XIV trimer

description: A collagen homotrimer of alpha1(XIV) chains; type XIV collagen triple helices may link sheet-forming or fibrillar collagens to other structures.


heavy chain immunoglobulin complex

description: A protein complex composed of two identical immunoglobulin heavy chains of the IgNAR isotype held together by disulfide bonds and lacking immunoglobulin light chains.


name: alpha5-beta1 integrin-tissue transglutaminase complex

description: A protein complex that consists of an alpha5-beta1 integrin complex bound to tissue transglutaminase.


ASAP complex

description: A protein complex involved in regulation of mRNA processing and apoptosis. It binds to RNA in a sequence-independent manner and is recruited to the EJC prior to or during the splicing process. In humans the core proteins are RNPS1, SAP18 and ACIN1.


alpha6-beta4 integrin-CD151 complex

description: A protein complex that consists of an alpha6-beta4 integrin complex bound to the tetraspanin CD151.


IgD B cell receptor complex

description: An IgD immunoglobulin complex that is present in the plasma membrane of B cells and is composed of two identical immunoglobulin heavy chains of the IgD isotype and two identical immunoglobulin light chains and a signaling subunit, a heterodimer of the Ig-alpha and Ig-beta proteins.


replication inhibiting complex

description: A protein complex that inhibits multiple events of replication initiation during one replication cycle.


polyketide synthase complex

description: A protein complex that carries out enzymatic reactions involved in the biosynthesis of polyketides, any of a diverse group of natural products synthesized via linear poly-beta-ketones.


interleukin-12 receptor complex

description: A protein complex that binds interleukin-12 and that consists of, at a minimum, a dimeric interleukin and its two receptor subunits as well as optional additional kinase subunits.


Grb2-SHP-2 complex

description: A protein complex that contains the receptor adaptor proteins Grb2 and SHP-2, and is involved signaling via the PDGFR signaling pathway.


CFTR-NHERF-ezrin complex

description: A protein complex that contains ezrin, Na+/H+ exchanger regulatory factor (NHERF, also called EBP50), and two copies of the cystic fibrosis transmembrane conductance regulator (CFTR). The CFTR molecules interact with NHERF via their cytoplasmic tail domains; the complex is thought to link the CFTR channel to the actin cytoskeleton and contribute to the regulation of channel activity.


eNoSc complex

description: A chromatin silencing complex that recruits histone-modifying enzymes and upregulates silencing of rDNA in response to glucose starvation.


Mre11 complex

description: Trimeric protein complex that possesses endonuclease activity; involved in meiotic recombination, DNA repair and checkpoint signaling. In Saccharomyces cerevisiae, the complex comprises Mre11p, Rad50p, and Xrs2p; complexes identified in other species generally contain proteins orthologous to the Saccharomyces cerevisiae proteins.


CSK-GAP-A.p62 complex

description: A protein complex that contains the protein-tyrosine kinase CSK and the GTPase-activating protein (GAP)-associated p62 (GAP-A.p62); may mediate translocation of proteins, including GAP and CSK, to membrane or cytoskeletal regions upon c-Src activation.


NLRP6 inflammasome complex

description: An inflammasome complex that consists of NLRP6, PYCARD/ASC and caspase-1 or caspase-4/caspase-11.


Smc5-Smc6 complex

description: A conserved complex that contains a heterodimer of SMC proteins (Smc5p and Smc6p, or homologs thereof) and several other proteins, and is involved in DNA repair and maintaining cell cycle arrest following DNA damage. In S. cerevisiae, this is an octameric complex called Mms21-Smc5-Smc6 complex, with at least five of its subunits conserved in fission yeast and humans.


description: Sodium:potassium-exchanging ATPases are tetrameric proteins, consisting of two large alpha subunits and two smaller beta subunits. The alpha subunits bear the active site and penetrate the membrane, while the beta subunits carry oligosaccharide groups and face the cell exterior.


cortical Lewy body

description: Cytoplasmic inclusion similar to a classical Lewy body but lacking a halo of protein fibrils.


inclusion body

description: A discrete intracellular part formed of aggregated molecules such as proteins or other biopolymers.


nucleolar peripheral inclusion body

description: Inclusion bodies located at the nucleolar periphery where several nuclear factors are reversibly aggregated and sequestered during acute heat stress or starvation.


classical Lewy body

description: Cytoplasmic inclusion, 5 to 15 micrometers in diameter, with a dense core surrounded by a halo of 10 to 20 nm wide radially oriented alpha-synuclein fibrils.


nematosome

description: Cytoplasmic, ball-like inclusion resembling a nucleolus and consisting of a convoluted network of electron-opaque strands embedded in a less dense matrix. It measures approximately 0.9 microns and lacks a limiting membrane. Its strands (diameter = 400-600 A) appear to be made of an entanglement of tightly packed filaments and particles approximately 25-50 A thick. Cytochemical studies suggest the presence of nonhistone proteins and some RNA. Usually only one such structure is present in a cell, and it appears to occur in most ganglion cells. Although they can be seen anywhere in the cell body, nematosomes are typically located in the perinuclear cytoplasm, where they are often associated with smooth-surfaced and coated vesicles.


skein-like inclusion

description: Intracytoplasmic filamentous structure frequently encountered in preparations immunostained for ubiquitin.


aggresome

description: An inclusion body formed by dynein-dependent retrograde transport of an aggregated protein on microtubules.


fibrillary inclusion

description: Cellular inclusion consisting of circular areas filled with fine slender filaments about 10 nanometers in diameter, delimited by a wall of varying complexity (either a single continuous membrane or a tubular network consisting of a fine filamentous material giving the wall a honeycomb appearance). Fibrillary inclusions are found in the cytoplasm of giant cells of Dieters in the lateral vestibular nucleus of the rat; similar structures have been described in the ventral cochlear nucleus, spinal cord, and substantia nigra.


neurofibrillary tangle

description: Intracellular mass of paired, helically wound protein filaments (also called PHF) lying in the cytoplasm of neuronal cell bodies and neuritic cell processes. Neurofibrillary tangles contain an abnormally phosphorylated form of a microtubule-associated protein, tau. The shape of these inclusions may resemble a flame or a star.


nuclear inclusion body

description: An intranuclear focus at which aggregated proteins have been sequestered.


glial cytoplasmic inclusion

description: Non-membrane-bound cytoplasmic inclusions composed of 10-40 nm granule-coated fibrils. These inclusions have an abnormal accumulation of alpha-synuclein protein and are found in association with multiple system atrophy.


Lewy body

description: Cytoplasmic, spherical inclusion commonly found in damaged neurons, and composed of abnormally phosphorylated, neurofilament proteins aggregated with ubiquitin and alpha-synuclein.


complex laminated body

description: A cytoplasmic inclusion body found in some lateral geniculate neurons and composed of sheets of tubules (25 nm in diameter) separated by dense material (about 75 nm wide), which together with the tubules whorl give a structure resembling a fingerprint.


laminated body

description: Inclusion body characterized by regularly spaced sheets of tubules arranged in a whorl pattern resembling a fingerprint. Laminated bodies have been observed in neurons of the lateral geniculate nucleus.


Pick body

description: Cellular inclusion composed of numerous tau fibrils arranged in a disorderly array. Tau protein is a major component, though Pick bodies also contain ubiquitin, alpha-synuclein, and apolipoprotein E.


hyaline inclusion

description: A glass-like, pale intracellular inclusion.


fibrillar center

description: A structure found most metazoan nucleoli, but not usually found in lower eukaryotes; surrounded by the dense fibrillar component; the zone of transcription from multiple copies of the pre-rRNA genes is in the border region between these two structures.


cnida

description: A giant secretory organelle that comprises a bulb-shape capsule containing a coiled hollow tubule structure attached to it. A cnida defines the phylum Cnidaria.


glutamatergic postsynaptic density

description: The post-synaptic specialization of a glutamatergic excitatory synapse.


presynaptic active zone membrane

description: The membrane portion of the presynaptic active zone; it is the site where docking and fusion of synaptic vesicles occurs for the release of neurotransmitters.


name: central plaque of mitotic spindle pole body

description: One of three laminate structures that form the mitotic spindle pole body; the inner plaque is on the nuclear face of the spindle pole body.


central plaque of spindle pole body

description: One of three laminate structures that form the spindle pole body; the central plaque is embedded in the nuclear envelope.


central region of growth cone

description: The center of the migrating motile tip of a growing nerve cell axon or dendrite.


cellular bud neck contractile ring

description: A contractile ring, i.e. a cytoskeletal structure composed of actin filaments and myosin, that forms beneath the plasma membrane at the mother-bud neck in mitotic cells that divide by budding in preparation for completing cytokinesis. An example of this structure is found in Saccharomyces cerevisiae.


extrahaustorial matrix

description: The space between the symbiont plasma membrane and the extrahaustorial membrane of the host.


glyoxysomal membrane

description: The lipid bilayer surrounding a glyoxysome.


glycosome membrane

description: The lipid bilayer surrounding a glycosome.


nucleus lagging edge

description: The area of a motile nucleus furthest from the direction of movement.


bleb

description: A cell extension caused by localized decoupling of the cytoskeleton from the plasma membrane and characterized by rapid formation, rounded shape, and scarcity of organelles within the protrusion. Blebs are formed during apoptosis and other cellular processes, including cell locomotion, cell division, and as a result of physical or chemical stresses.


mannosome

description: A specialised tubular organelle, assembled in hexagonal bundles within an external membrane. Mannosomes are specific to molluscs and are thought to be involved in a general stress reaction.


ribbon synapse

description: Type of synapse characterized by an electron-dense ribbon, lamella (bar) or spherical body in the presynaptic process cytoplasm.


photoreceptor ribbon synapse

description: A ribbon synapse between a retinal photoreceptor cell (rod or cone) and a retinal bipolar cell. These contain a plate-like synaptic ribbon.


cochlear hair cell ribbon synapse

description: A ribbon synpase of an auditory hair cell of the cochlear. These ribbon synapses contain spherical synaptic ribbons and lack and arciform density.


name: extrinsic component of postsynaptic membrane

description: The component of the postsynaptic membrane consisting of gene products and protein complexes that are loosely bound to one of its surfaces, but not integrated into the hydrophobic region.


extrinsic component of plasma membrane

description: The component of a plasma membrane consisting of gene products and protein complexes that are loosely bound to one of its surfaces, but not integrated into the hydrophobic region.


name: extrinsic component of presynaptic membrane

description: The component of the presynaptic membrane consisting of gene products and protein complexes that are loosely bound to one of its surfaces, but not integrated into the hydrophobic region.


name: extrinsic component of presynaptic endocytic zone membrane

description: The component of the presynaptic endocytic zone membrane consisting of gene products and protein complexes that are loosely bound to one of its surfaces, but not integrated into the hydrophobic region.


name: extrinsic component of postsynaptic specialization membrane

description: The component of the postsynaptic specialization membrane consisting of gene products and protein complexes that are loosely bound to one of its surfaces, but not integrated into the hydrophobic region.


name: extrinsic component of postsynaptic density membrane

description: The component of the postsynaptic density membrane consisting of gene products and protein complexes that are loosely bound to one of its surfaces, but not integrated into the hydrophobic region.


name: extrinsic component of cytoplasmic side of plasma membrane

description: The component of a plasma membrane consisting of gene products and protein complexes that are loosely bound to its cytoplasmic surface, but not integrated into the hydrophobic region.


name: extrinsic component of external side of plasma membrane

description: The component of a plasma membrane consisting of gene products and protein complexes that are loosely bound to its external surface, but not integrated into the hydrophobic region.


name: extrinsic component of presynaptic active zone membrane

description: The component of the presynaptic active zone membrane consisting of gene products and protein complexes that are loosely bound to one of its surfaces, but not integrated into the hydrophobic region.


name: extrinsic component of synaptic membrane

description: The component of the synaptic membrane consisting of gene products and protein complexes that are loosely bound to one of its surfaces, but not integrated into the hydrophobic region.


name: extrinsic component of postsynaptic endocytic zone

description: The component of the postsynaptic endocytic zone membrane consisting of gene products and protein complexes that are loosely bound to one of its surfaces, but not integrated into the hydrophobic region.


bacterial microcompartment

description: An organelle found in bacteria consisting of a proteinaceous coat containing metabolic enzymes whose purpose is the sequestration or concentration of metabolites and which has the appearance of a polygonal granule by electron microscopy.


perinucleolar chromocenter

description: A chromocenter adjacent to the nucleolus.


meiotic spindle

description: A spindle that forms as part of meiosis. Several proteins, such as budding yeast Spo21p, fission yeast Spo2 and Spo13, and C. elegans mei-1, localize specifically to the meiotic spindle and are absent from the mitotic spindle.


mitochondrial nucleoid

description: The region of a mitochondrion to which the DNA is confined.


protein aggregate center

description: Reversible aggregate of misfolded proteins and chaperones formed to shield thermosensitive proteins from degradation until conditions allow disaggregation and refolding.


crystalloid

description: A transient, cytoplasmic organelle found in Plasmodium species that resembles a cytoplasmic inclusion body and whose function is poorly understood. Crystalloids form in ookinetes and disappear after ookinete-to-oocyst transformation.


arciform density

description: An electron dense structure that anchors a synaptic ribbon to the presynaptic membrane.


monolayer-surrounded lipid storage body

description: A subcellular organelle of plant cells surrounded by 'half-unit' or a monolayer membrane instead of the more usual bilayer. The storage body has a droplet of triglyceride surrounded by a monolayer of phospholipids, interacting with the triglycerides and the hydrophilic head groups facing the cytosol, and containing major protein components called oleosins.


mitochondrial chromosome

description: A chromosome found in the mitochondrion of a eukaryotic cell.


Z chromosome

description: The sex chromosome present in both sexes of species in which the female is the heterogametic sex. Two copies of the Z chromosome are present in each somatic cell of males and one copy is present in females.


spectrosome

description: A germline specific spherical organelle, rich in membrane skeletal proteins. Precursor to the fusome.


sex chromosome

description: A chromosome involved in sex determination.


ascus lipid droplet

description: Any particle of coalesced lipids in an ascus or ascospore. May include associated proteins.


Barr body

description: A structure found in a female mammalian cell containing an unpaired X chromosome that has become densely heterochromatic, silenced and localized at the nuclear periphery.


chloroplast nucleoid

description: The region of a chloroplast to which the DNA is confined.


chloroplast stromal thylakoid

description: Unstacked thylakoids that connect the grana stacks through the stroma.


plastid ribosome

description: A ribosome contained within a plastid.


XY body

description: A structure found in a male mammalian spermatocyte containing an unpaired X chromosome that has become densely heterochromatic, silenced and localized at the nuclear periphery.


pyrenoid

description: A non-membrane-bounded organelle found within the chloroplasts of algae and hornworts; responsible for carbon dioxide fixation.


carboxysome

description: An organelle consisting of a proteinaceous coat and enzymes for the fixation of CO2. It augments the concentration of CO2 in the vicinity of RuBisCO to increase the efficiency of CO2 fixation under atmospheric conditions.


bacterial nucleoid

description: The region of a bacterial cell to which the DNA is confined.


goblet cell theca

description: A cup shaped specialization of the cytoskeleton that forms a thin layer located just below the apical mass of mature mucin secretory granules in the cytoplasm of goblet cells of the intestinal epithelium. It consists of an orderly network of intermediate filaments and microtubules. Microtubules are arranged vertically, like barrel staves, along the inner aspect of the theta. Intermediate filaments form two networks: an inner, basketlike network and an outer series of circumferential bundles resembling the hoops of a barrel.


synaptic ribbon

description: A non-membrane bound, electron dense structure associated that extends perpendicular to the presynaptic membrane in ribbon synapses. The ribbon's surface is studded with small particles to which synaptic vesicles tether via fine filaments. The tethered vesicles function as a pool, several fold greater than the docked pool available for fast release, which supports sustained release of vesicles. Synaptic ribbons may be plate like or spherical.


proplastid nucleoid

description: The region of a proplastid to which the DNA is confined.


Y chromosome

description: The sex chromosome present in males of species in which the male is the heterogametic sex; generally, the sex chromosome that pairs with the X chromosome in the heterogametic sex. The Y chromosome is absent from the cells of females and present in one copy in the somatic cells of males.


chloroplast thylakoid

description: Sac-like membranous structures (cisternae) in a chloroplast combined into stacks (grana) and present singly in the stroma (stroma thylakoids or frets) as interconnections between grana. An example of this component is found in Arabidopsis thaliana.


active sex chromosome

description: A sex chromosome that has not been inactivated.


polytene chromosome chromocenter

description: A region at which the centric regions of polytene chromosomes are joined together.


cyanelle thylakoid

description: A thylakoid found in a cyanelle, which is a type of plastid found in certain algae. The cyanelle contains a photosynthetic membrane resembling that of cyanobacteria.


prothylakoid

description: Underdeveloped thylakoids found in etioplasts, lacking competent photosynthetic membranes. Rapidly develop into mature thylakoids in the presence of light.


bacterial thylakoid

description: A thylakoid that is derived from and attached to, but not necessarily continuous with, the plasma membrane, and is not enclosed in a plastid. It bears the photosynthetic pigments in photosynthetic cyanobacteria.


gas vesicle

description: An intracellular non-membrane-bounded organelle; a hollow structure made of protein, which usually has the form of a cylindrical tube closed by conical end caps. By regulating their relative gas vesicle content, aquatic microbes are able to perform vertical migrations.


nucleolus-like body

description: A nuclear compartment containing significant amounts of non-nucleolar, spliceosomal components. It is commonly found in germinal vesicle (GV) stage oocytes, and is similar to both nucleoli and sphere organelles.


dynein axonemal particle

description: An aggregation of axonemal dyneins, their specific assembly factors, and broadly-acting chaperones that is located in the cytoplasm.


autosome

description: Any chromosome other than a sex chromosome.


thylakoid

description: A membranous cellular structure that bears the photosynthetic pigments in plants, algae, and cyanobacteria. In cyanobacteria thylakoids are of various shapes and are attached to, or continuous with, the plasma membrane. In eukaryotes they are flattened, membrane-bounded disk-like structures located in the chloroplasts; in the chloroplasts of higher plants the thylakoids form dense stacks called grana. Isolated thylakoid preparations can carry out photosynthetic electron transport and the associated phosphorylation.


organellar chromatophore thylakoid

description: A thylakoid located in an organellar chromatophore.


plastid thylakoid

description: Any thylakoid within a plastid.


plastid nucleoid

description: The region of a plastid to which the DNA is confined.


name: propanediol degradation polyhedral organelle

description: An organelle found in bacteria consisting of a proteinaceous coat containing enzymes for the degradation of 1,2-propanediol whose purpose is the protection of the rest of the cell from the toxic propionaldehyde product of the enzyme diol dehydratase.


chlorosome

description: A large enclosure of aggregated pigment, typically bacteriochlorophyll c (BChl c), that acts as a light-harvesting antenna structure and is characteristic of green photosynthetic bacteria (e.g. Chlorobiaceae). The BChl aggregates are organized into lamellar elements by pigment-pigment rather than pigment-protein interactions. Chlorosomes also contain BChl a, carotenoids, quinones, lipids, and proteins, and are attached to the cytoplasmic membrane via a BChl a-containing protein baseplate.


ventral disc

description: Specialized organelle found in Giardia species (trophozoite stage) and characterized by a spiral array of microtubules and microtubule-associated structures including dorsal microribbons and crossbridges. The edge of the ventral disc narrows into a lateral crest. The ventral disk mediates mechanical attachment of the trophozoite to the host's intestinal wall, and contains the contractile proteins actinin, alpha-actinin, myosin, and tropomyosin working towards contraction of the disk involved in adherence.


nematocyst

description: An organelle found in cnidoblast (nematoblast) cells. When matured, these stinging organelles store toxins and can deliver them when the cnidocil (a short extension of the cnidocyst) is stimulated by a prey or another stimulus.


W chromosome

description: The sex chromosome present in females of species in which the female is the heterogametic sex; generally, the sex chromosome that pairs with the Z chromosome in the heterogametic sex. The W chromosome is absent from the cells of males and present in one copy in the somatic cells of females.


inactive sex chromosome

description: A sex chromosome that has been inactivated.


X chromosome

description: The sex chromosome present in both sexes of species in which the male is the heterogametic sex. Two copies of the X chromosome are present in each somatic cell of females and one copy is present in males.


blepharoplast

description: An intracellular non-membrane-bounded organelle found in multi-ciliated sperm cells of some primitive land plants, and consisting of many radially arranged ninefold symmetric cylinders. The blepharoplast is involved in de novo formation of multiple centrioles; it enlarges and then disintegrates into many procentrioles, which elongate and ultimately nucleate cilia on the surface of the sperm cell.


polytene chromosome

description: A type of chromosome in a polyploid cell, formed when multiple copies of homologous chromosomes are aligned side by side to give a giant chromosome in which distinct chromosome bands are readily visible.


granal stacked thylakoid

description: Appressed thylakoid membranes that are part of a granum (stacked regions). A characteristic of these appressed regions is the preferential localization of photosystem II.


chromocenter

description: A region in which centric, heterochromatic portions from more than one chromosomes form a compact structure.


podosome

description: An actin-rich adhesion structure characterized by formation upon cell substrate contact and localization at the substrate-attached part of the cell, contain an F-actin-rich core surrounded by a ring structure containing proteins such as vinculin and talin, and have a diameter of 0.5 mm.


proteasome storage granule

description: An aggregation of proteasome core protease (CP) and regulatory particle (RP) complexes that localizes in the cytoplasm as dot-like structures when cells are in a quiescent state.


elaioplast

description: A leucoplast in which oil is stored.


histone locus body

description: A nuclear body associated with the histone gene locus that is thought to contain all of the factors necessary for histone mRNA transcription and pre-mRNA processing. In Drosophila, U7 snRNP is located in the histone locus body rather than the distinct Cajal body.


mitotic nuclear bridge

description: A narrow constricted region of the nucleus that forms around the anaphase spindle during closed mitosis, and connects the main portions of the newly forming daughter nuclei.


host cell rough endoplasmic reticulum

description: The irregular network of unit membranes, visible only by electron microscopy, that occurs in the host cell cytoplasm of many eukaryotic cells. The membranes form a complex meshwork of tubular channels, which are often expanded into slitlike cavities called cisternae. The host rough ER has ribosomes adhering to the outer surface.


amphisome membrane

description: Any membrane that is part of an amphisome.


name: extrinsic component of external side of mycolate outer membrane

description: The component of mycolate membrane consisting of gene products and protein complexes that are loosely bound to its external surface, but not integrated into the hydrophobic region.


name: extrinsic component of mycolate outer membrane

description: The component of mycolate outer membrane consisting of gene products and protein complexes that are loosely bound to one of its surfaces, but not integrated into the hydrophobic region.


name: alae of collagen and cuticulin-based cuticle extracellular matrix

description: Raised, thickened cuticular ridges that run longitudinally, and in parallel, along the left and right sides of the animal. The alae lie above the hypodermal cells known as the lateral seam cells. In C. elegans, alae are produced in L1 larvae, dauer larvae and adult stage animals, where they consist of three, five, and three ridges of distinct morphology, respectively.


host multivesicular body

description: A late endosome in which regions of the limiting host cell endosomal membrane invaginate to form internal vesicles; host membrane proteins that enter the internal vesicles are sequestered from the host cytoplasm.


host cell late endosome

description: A prelysosomal endocytic organelle differentiated from host early endosomes by lower lumenal pH and different protein composition. Host late endosomes are more spherical than early endosomes and are mostly juxtanuclear, being concentrated near the microtubule organizing center.


polar tube

description: A highly specialized structure unique to microsporidia that is required for host cell invasion. In the spore, the polar tube is connected at the anterior end, and then coils around the sporoplasm. Upon appropriate environmental stimulation, the polar tube rapidly discharges out of the spore, pierces a cell membrane and serves as a conduit for sporoplasm passage into the new host cell.


endospore coat

description: The layer in a bacterial endospore that lies under the exosporium, and is impermeable to many toxic molecules. The coat may also contain enzymes that are involved in endospore germination.


leucoplast stroma

description: The space enclosed by the double membrane of a leucoplast.


linear element

description: A proteinaceous scaffold associated with fission yeast chromosomes during meiotic prophase. Linear elements consist of a protein complex, LinE, with four main structural components (Rec10, Rec25, Rec27, and Mug20 in S. pombe) associated with chromatin. The resulting structure is related to but not equivalent to the synaptonemal complex.


amyloplast inner membrane

description: The inner, i.e. lumen-facing, lipid bilayer of the amyloplast envelope; also faces the amyloplast stroma.


perisynaptic space

description: The extracellular region immediately adjacent to to a synapse.


megagametophyte egg cell nucleus

description: The nucleus of a plant egg cell. This nucleus is found at the micropylar end of the embryo.


lignin network

description: An extracellular matrix part that consists of lignin in the form of a three-dimensional polymeric network. Lignins are complex racemic aromatic heteropolymers derived from a variety of phenylpropane monomers coupled together by an assortment of carbon-carbon and ether linkages. Lignin is crucial for structural integrity of the cell wall and stiffness and strength of the stem. In addition, lignin waterproofs the cell wall, enabling transport of water and solutes through the vascular system, and plays a role in protecting plants against pathogens.


hyphal septin band

description: A septin band, i.e. a diffuse ring composed of a series of septin bars running parallel to the long axis of the cell, located at the junction between the mother cell and the germ tube (hypha) of a fungal cell growing filamentously.


pilus shaft

description: The long, slender, mid section of a pilus.


lower tip-link density

description: An electron-dense plaque at the lower end of a stereocilia tip link that provides the anchor in the stereocilia membrane at the tip of the stereocilium from which the tip link rises.


sieve area

description: A pit-like area in the cell wall of a sieve element; contains pores lined with callose and occupied by strands of protoplasmic material that interconnect the protoplasts of contiguous sieve elements.


host cell PML body

description: A nuclear body that reacts against SP100 auto-antibodies (PML = promyelocytic leukemia) located within a cell of a host organism.


nucleoplasmic side of nuclear pore

description: The side of the nuclear pore complex (NPC) that faces the nucleoplasm.


autolysosome

description: A type of secondary lysosome in which a primary lysosome has fused with the outer membrane of an autophagosome or amphisome. It is involved in the second step of autophagy in which it degrades contents with acidic lysosomal hydrolases.


secondary lysosome

description: Vacuole formed by the fusion of a lysosome with an organelle (autosome) or with a primary phagosome.


left lateral basal body pair

description: Set of two basal bodies found in Giardia species (trophozoite stage). It comprises the anterior and ventral basal bodies located to the right of the left nucleus of the trophozoite when viewed dorsally.


host cell centrosome

description: A structure in a host cell comprised of a core structure (in most organisms, a pair of centrioles) and peripheral material from which a microtubule-based structure, such as a spindle apparatus, is organized. Centrosomes occur close to the nucleus during interphase in many eukaryotic cells, though in animal cells it changes continually during the cell-division cycle.


stereocilia tip link

description: A stereocilia link that is formed by a fine filament running more or less vertically upward from the tip of each shorter stereocilium to attach at a higher point on its adjacent taller neighbor. Tilting the bundle puts tension on the filaments, which pull on mechanically gated ion channels in the membrane of the stereocilia.


axonemal outer doublet

description: Part of an axoneme consisting in a doublet microtubule. Nine of these outer doublets form the 9+0 axoneme, while the 9+2 axoneme also contains a central pair. Dynein arms attached to the doublets provide the mechanism of movement of the cilium.


thorny excrescence

description: Large complex spine protruding from a dendrite. Each excrescence is formed by a cluster of spine heads.


postsynapse of neuromuscular junction

description: The postsynapse of a neuromuscular junction. In vertebrate muscles this includes the motor end-plate, consisting of postjunctional folds of the sarcolemma.


dinoflagellate sulcus

description: A cell surface furrow that occurs on the ventral side of a dinoflagellate cell. It partially houses the longitudinal flagellum. The sulcus intersects with the cingulum on the ventral side of a dinoflagellate cell.


cell surface furrow

description: A furrow that may be found on the cell surface. Examples include the cingulum and sulcus found in some dinoflagellates.


dinoflagellate cingulum

description: A cell surface furrow that wraps around a dinoflagellate cell; the transverse flagellum lies in it.


dinoflagellate sulcal notch

description: A dinoflagellate sulcus that extends all the way to the posterior end of the cell (also known as antapex). The presence of a sulcal notch makes the dinoflagellate hypocone appear bilobed.


dinoflagellate apical groove

description: A cell surface furrow (or groove) found on a dinoflagellate apex. It typically loops around the apex.


attachment organelle membrane

description: The lipid bilayer surrounding an attachment organelle. This is a region of the cell membrane facing the environment - in mycoplasma, part of the mycolate outer membrane.


host cell filopodium

description: Thin, stiff protrusion extended by the leading edge of a motile host cell such as a crawling fibroblast or amoeba, or an axonal growth cone; usually approximately 0.1 um wide, 5-10 um long, can be up to 50 um long in axon growth cones; contains a loose bundle of about 20 actin filaments oriented with their plus ends pointing outward.


host cell projection

description: A prolongation or process extending from a host cell, e.g. a flagellum or axon.


host cell uropod

description: A host cell membrane projection with related cytoskeletal components at the trailing edge of a cell in the process of migrating or being activated, found on the opposite side of the cell from the leading edge or immunological synapse, respectively.


microtubule minus-end

description: The end of a microtubule that does not preferentially grow (polymerize).


microtubule end

description: Any end of a microtubule. Microtubule ends differ in that the so-called microtubule plus-end is the one that preferentially grows by polymerization, with respect to the minus-end.


post-anaphase array microtubule end

description: Any microtubule end that is part of a post-anaphase array microtubule.


mitotic spindle astral microtubule end

description: Any microtubule end that is part of a mitotic spindle astral microtubule.


cytoplasmic microtubule minus-end

description: A microtubule minus end that is part of a cytoplasmic microtubule.


plasmodesmatal endoplasmic reticulum

description: Endoplasmic reticulum found in plasmodesmata, junctions connecting the cytoplasm of adjacent plant cells.


smooth endoplasmic reticulum

description: The smooth endoplasmic reticulum (smooth ER or SER) has no ribosomes attached to it. The smooth ER is the recipient of the proteins synthesized in the rough ER. Those proteins to be exported are passed to the Golgi complex, the resident proteins are returned to the rough ER and the lysosomal proteins after phosphorylation of their mannose residues are passed to the lysosomes. Glycosylation of the glycoproteins also continues. The smooth ER is the site of synthesis of lipids, including the phospholipids. The membranes of the smooth ER also contain enzymes that catalyze a series of reactions to detoxify both lipid-soluble drugs and harmful products of metabolism. Large quantities of certain compounds such as phenobarbital cause an increase in the amount of the smooth ER.


membrane stack

description: A configuration of endoplasmic reticulum (ER) found in Purkinje cells in the cerebellum and in axons in the lateral vestibular nucleus, consisting of parallel and interconnecting tubules whose outer surfaces are covered by particles or ringlike structures.


name: interphase microtubule organizing center

description: A microtubule organizing center found in interphase cells, which organize a longitudinal array of three to five MT bundles from the nuclear envelope during interphase. Each MT bundle is composed of two to seven MTs arranged in an antiparallel configuration, with the dynamic MT plus ends extending toward the cell tips and stable minus ends near the nucleus.


host intracellular part

description: Any constituent part of the living contents of a host cell; the matter contained within (but not including) the plasma membrane, usually taken to exclude large vacuoles and masses of secretory or ingested material. In eukaryotes it includes the nucleus and cytoplasm. The host is defined as the larger of the organisms involved in a symbiotic interaction.


host chromosome

description: A structure composed of a very long molecule of DNA and associated proteins (e.g. histones) that carries hereditary information, occurring within a host cell.


host cell nucleus

description: A membrane-bounded organelle as it is found in the host cell in which chromosomes are housed and replicated. The host is defined as the larger of the organisms involved in a symbiotic interaction.


host cell synaptic vesicle

description: A secretory organelle of a host cell, some 50 nm in diameter, of presynaptic nerve terminals; accumulates in high concentrations of neurotransmitters and secretes these into the synaptic cleft by fusion with the 'active zone' of the presynaptic plasma membrane.


Maurer's cleft

description: A disk-like structure that appears at the periphery of a red blood cell infected by an apicomplexan parasite, characterized by a translucent lumen and an electron-dense coat of variable thickness; often appears to be tethered to the host cell membrane by fibrous connections with the erythrocyte cytoskeleton.


viral replication complex

description: Specific locations and structures in the virus infected cell involved in replicating the viral genome.


host cell nucleolus

description: A small, dense body one or more of which are present in the nucleus of eukaryotic host cells.


name: host cell mitochondrial intermembrane space

description: The region between the inner and outer lipid bilayers of the host cell mitochondrial envelope.


host cell plastid

description: Any member of a family of organelles as found in the cytoplasm of host cells, which are membrane-bounded and contain DNA. The host is defined as the larger of the organisms involved in a symbiotic interaction.


host cell nucleoplasm

description: That part of a host cell's nuclear content other than the chromosomes or the nucleolus. The host is the larger of the organisms involved in a symbiotic interaction.


host symbiosome

description: A double-enveloped cell compartment, composed of the endosymbiont with its plasmalemma (as inner envelope) and an outer envelope (the perisymbiontic membrane) derived from the host cell.


host cell endoplasmic reticulum lumen

description: The volume enclosed by the membranes of the host cell endoplasmic reticulum.


host cell synaptic vesicle membrane

description: The lipid bilayer surrounding a host synaptic vesicle.


host cell nuclear lamina

description: The fibrous, electron-dense layer lying on the nucleoplasmic side of the inner membrane of a host cell nucleus, composed of lamin filaments.


host cell peroxisome

description: A small host cell organelle enclosed by a single membrane, and found in most eukaryotic cells. Contains peroxidases and other enzymes involved in a variety of metabolic processes including free radical detoxification, lipid catabolism and biosynthesis, and hydrogen peroxide metabolism.


host cell endosome lumen

description: The volume enclosed by the membranes of the host cell endosome.


host cell mitochondrion

description: A semiautonomous, self replicating organelle as found in host cells that occurs in varying numbers, shapes, and sizes in the cell cytoplasm. The host is defined as the larger of the organisms involved in a symbiotic interaction.


name: host cell perinuclear region of cytoplasm

description: The host cell cytoplasm situated near, or occurring around, the host nucleus.


host thylakoid membrane

description: The pigmented membrane of any host thylakoid.


host cell cytoplasmic vesicle

description: A vesicle formed of membrane or protein, found in the cytoplasm of a host cell.


host cell lysosome

description: A small lytic vacuole that has cell cycle-independent morphology and is found in most host animal cells and that contains a variety of hydrolases, most of which have their maximal activities in the pH range 5-6. The contained enzymes display latency if properly isolated. About 40 different lysosomal hydrolases are known and host cell lysosomes have a great variety of morphologies and functions.


host cell nuclear part

description: Any constituent part of a host cell's nucleus, a membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. The host is the larger of the organisms involved in a symbiotic interaction.


host cell lipid droplet

description: Any particle of coalesced lipids in the cytoplasm of a host cell. May include associated proteins.


host cell Cajal body

description: A class of nuclear body in the eukaryotic host cell, first seen after silver staining by Ramon y Cajal in 1903, enriched in small nuclear ribonucleoproteins, and certain general RNA polymerase II transcription factors; ultrastructurally, they appear as a tangle of coiled, electron-dense threads roughly 0.5 micrometers in diameter; involved in aspects of snRNP biogenesis; the protein coilin serves as a marker for Cajal bodies. Some argue that Cajal bodies are the sites for preassembly of transcriptosomes, unitary particles involved in transcription and processing of RNA. The host is the larger of the organisms involved in a symbiotic interaction.


host intracellular organelle

description: Organized structure of distinctive morphology and function, occurring within the host cell. Includes the nucleus, mitochondria, plastids, vacuoles, vesicles, ribosomes and the cytoskeleton. Excludes the plasma membrane. The host is defined as the larger of the organisms involved in a symbiotic interaction.


host cell smooth endoplasmic reticulum

description: The irregular network of unit membranes, visible only by electron microscopy, that occurs in the host cell cytoplasm of many eukaryotic cells. The membranes form a complex meshwork of tubular channels, which are often expanded into slitlike cavities called cisternae. The host smooth ER has no ribosomes adhering to the outer surface.


host cell mitochondrial envelope

description: The double lipid bilayer enclosing the host cell mitochondrion and separating its contents from the host cell cytoplasm; includes the intermembrane space.


symbiont-containing vacuole

description: Membrane-bounded vacuole within a host cell in which a symbiont organism resides. The vacuole membrane is derived from both the host and symbiont.


host cytoskeleton

description: A cellular structure that forms the internal framework of eukaryotic and prokaryotic host cells. The cytoskeleton includes intermediate filaments, microfilaments, microtubules, the microtrabecular lattice, and other structures characterized by a polymeric filamentous nature and long-range order within the cell. The various elements of the cytoskeleton not only serve in the maintenance of cellular shape but also have roles in other cellular functions, including cellular movement, cell division, endocytosis, and movement of organelles.


host cell cytoplasmic vesicle membrane

description: The lipid bilayer surrounding a host cell cytoplasmic vesicle.


host cell endosome

description: A membrane-bounded organelle that carries materials newly ingested by endocytosis. It passes many of the materials to host cell lysosomes for degradation.


host cell nuclear matrix

description: The dense fibrillar network lying on the inner side of the host nuclear membrane.


name: double membrane vesicle viral factory lumen

description: The volume surrounded by the inner membrane of a double membrane vesicle viral factory.


host cell cytoplasm part

description: Any constituent part of the host cell cytoplasm, all of the contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures. The host is defined as the larger of the organisms involved in a symbiotic interaction.


host cell endoplasmic reticulum

description: The irregular network of unit membranes, visible only by electron microscopy, that occurs in the host cell cytoplasm of many eukaryotic cells. The membranes form a complex meshwork of tubular channels, which are often expanded into slitlike cavities called cisternae. The host ER takes two forms, rough (or granular), with ribosomes adhering to the outer surface, and smooth (with no ribosomes attached).


host cell cytosol

description: The part of the host cell cytoplasm that does not contain organelles but which does contain other particulate matter, such as protein complexes.


host cell viral nucleoid

description: The region of a host cell that contains the viral genome.


name: host intracellular membrane-bounded organelle

description: Organized structure of distinctive morphology and function, as found in host cells, bounded by a single or double lipid bilayer membrane and occurring within the cell. Includes the nucleus, mitochondria, plastids, vacuoles, and vesicles. Excludes the plasma membrane. The host is defined as the larger of the organisms involved in a symbiotic interaction.


host thylakoid

description: A membranous cellular structure within the host cell that bears the photosynthetic pigments in plants, algae, and cyanobacteria. In cyanobacteria thylakoids are of various shapes and are attached to, or continuous with, the host plasma membrane. In eukaryotic host cells they are flattened, membrane-bounded disk-like structures located in the chloroplasts; in the chloroplasts of higher plants the thylakoids form dense stacks called grana. Isolated thylakoid preparations can carry out photosynthetic electron transport and the associated phosphorylation.


name: postsynaptic specialization membrane of symmetric synapse

description: The membrane component of the postsynaptic specialization of a symmetric synapse. This is the region of the postsynaptic membrane in which the population of neurotransmitter receptors involved in synaptic transmission are concentrated.


nucleoid

description: The region of a virus, bacterial cell, mitochondrion or chloroplast to which the nucleic acid is confined.


type Ib terminal bouton

description: Terminal inflated portion of the axon of a glutamatergic neuron, containing the specialized apparatus necessary for the tonic release neurotransmitters that will induce the contraction of muscle. Type Ib terminal boutons are larger than type Is terminal boutons.


basal distal dendrite

description: Any dendrite in a dendritic tree that emerges near the basal pole of a neuron (e.g. in bipolar neurons, basal dendrites are either on the same side of the soma as the axon, or project toward the axon), and which is farthest away from the neuronal cell body (the soma).


cell wall-bounded periplasmic space

description: The region between the plasma membrane and the cell wall in organisms lacking an outer cell membrane such as yeast and Gram positive bacteria. The region is thinner than the equivalent in Gram negative bacteria.


name: monolayer-surrounded lipid storage body outer lipid monolayer

description: The single layer of phopholipids surrounding a lipid storage body.


left posteriolateral flagellum

description: A cilium (also called flagellum) found in Giardia species (trophozoite stage). It is nucleated by the left posteriolateral basal body and extends cytoplasmically toward the cell posterior, marking the left anterior boundary of the lateral shield and the left lateral region of the funis before exiting at the left lateral region of the cell body.


dendritic branch

description: A dendrite arising from another dendrite.


postsynaptic Golgi apparatus

description: The network of the Golgi apparatus structures located within the postsynapse.


hyphal tip

description: The end, or tip, of a fungal hypha, where polarized growth occurs during hyphal elongation.


nucleolar chromatin

description: The portion of nuclear chromatin associated with the nucleolus; includes the DNA encoding the ribosomal RNA.


nucleolus-associated heterochromatin

description: Dense particles of heterochromatin, consisting of a loosely twisted strand about 600 Angstrom thick, found associated with the nucleolus.


nucleolus organizer region

description: A region of a chromosome where nucleoli form during interphase, and where genes encoding the largest rRNA precursor transcript are tandemly arrayed.


dendritic spine neck

description: Part of the dendritic spine that connects the dendritic shaft to the head of the dendritic spine.


S bouton

description: Synaptic bouton found in the ventral horn of the spinal cord. S boutons range in diameter from 0.5 to 8 um and contain spherical synaptic vesicles.


outer mucus layer

description: The outer of two mucus layers secreted by epithelial cells in the colon; the outer mucus layer is loosely packed and can be colonized by bacteria.


omegasome membrane

description: Any membrane that is part of an omegasome.


smooth endoplasmic reticulum cisterna

description: A subcompartment of the smooth endoplasmic reticulum consisting of lumenal expansion into a flattened, disc-shaped cavity.


subrhabdomeral cisterna

description: A membrane-bounded compartment that is found at the base of the rhabdomere and contains stored calcium, InsP3 receptors and smooth endoplasmic reticulum Ca2+-ATPase.


sub-surface cisterna

description: Specialization of the hypolemmal cisterna consisting of either single profiles or closely apposed stacks of endoplasmic reticulum in which the lumen is obliterated, lying 10-20 nm beneath the plasma membrane.


hypolemmal cisterna

description: Specialized part of the smooth endoplasmic reticulum that closely underlies the plasma membrane, usually within 60 nm or closer.


pseudopodium membrane

description: The portion of the plasma membrane surrounding a pseudopodium.


ciliary pocket

description: Invagination of the plasma membrane from which a cilium (also called flagellum) protrudes.


caveola neck

description: A membrane microdomain that forms a necklace around the bulb (crater) of a caveola. Intramembrane particles are concentrated in this region and cytoskeletal components, including actin, are highly enriched in the area underlying it.


eisosome membrane domain/MCC

description: A plasma membrane part that is composed of a furrow-like plasma membrane domain and associated integral transmembrane proteins.


dendritic spine membrane

description: The portion of the plasma membrane surrounding a dendritic spine.


host peribacteroid membrane

description: A host-derived membrane that surrounds one or more bacteroids (such as nitrogen-fixing bacteroids within legume root nodule cells).


transverse flagellum

description: A motile cilium found in dinoflagellates. It coils around the cell and provides the forward thrust for motility. It is often contained in a furrow called the cingulum, and emerges from a flagellar pore located in the cingulum.


sculpture element

description: The third layer of the sexine.


platelet glycocalyx

description: The carbohydrate rich layer at the outermost periphery of a platelet.


right tetrad

description: Set of four basal bodies found in Giardia species (trophozoite stage). It comprises the right lateral basal body pair and the right middle basal body pair (i.e. the anterior, ventral, caudal and posteriolateral basal bodies located to the left of the right nucleus of the trophozoite when viewed dorsally).


name: ventral disc supernumerary microtubule array

description: A partial left-handed spiral array of microtubules that lies generally dorsal to the main ventral disc microtubule array in Giardia species (trophozoite stage).


axonemal central pair

description: Part of the axoneme consisting of the inner two microtubule doublets of the 9+2 axoneme occurring in most motile cilia.


endocytic vesicle lumen

description: The volume enclosed by the membrane of an endocytic vesicle.


phagocytic vesicle lumen

description: The volume enclosed by the membrane of a phagocytic vesicle.


clathrin-coated endocytic vesicle lumen

description: The volume enclosed by the membrane of a clathrin-coated endocytic vesicle.


early phagosome lumen

description: The volume enclosed by the membrane of an early phagosome.


host cell surface

description: The external part of the host cell wall and/or host plasma membrane.


host apoplast

description: The apoplast region surrounding a host plant cell. Plants may be described as having two major compartments: the living symplast and the non-living apoplast. The apoplast is external to the plasma membrane and includes cell walls, intercellular spaces and the lumen of dead structures such as xylem vessels. Water and solutes pass freely through it. The host is defined as the larger of the organisms involved in a symbiotic interaction.


left ventral basal body

description: Any ciliary basal body that is part of a left ventral flagellum found in Giardia species (trophozoite stage).


respiratory system basement membrane

category: biolink:AnatomicalEntity biolink:PhysicalEssence biolink:OrganismalEntity biolink:SubjectOfInvestigation biolink:BiologicalEntity biolink:ThingWithTaxon biolink:NamedThing biolink:PhysicalEssenceOrOccurrent

description: A basement membrane of epithelium that is part of a respiratory system.


acellular membrane

description: An acellular anatomical structure that is the bounding layer of a anatomical structure.


endospore-forming forespore

description: Portion of the cell formed during the process of bacterial sporulation that will ultimately become the core of the endospore. An endospore is a type of dormant cell that is resistant to adverse conditions.


inner layer of spore wall

description: Either of the two innermost layers of the spore wall, as described in Saccharomyces.


9+2 non-motile cilium

description: A non-motile cilium where the axoneme has a ring of nine outer microtubule doublets plus two central microtubules (and is therefore called a 9+2 axoneme).


granum

description: Distinct stack of lamellae seen within chloroplasts. Grana contain the pigments, electron transfer compounds, and enzymes essential to the light-dependent reactions of photosynthesis.


internode region of axon

description: An axon part that is located between the nodes of Ranvier and surrounded by compact myelin sheath.


cleavage body

description: A nuclear body that contains proteins involved in pre-mRNA 3'-end cleavage and polyadenylation, such as DDX1, CSTF2 and CPSFs, as well as the transcription factors TFIIE and TFIIF. Cleavage bodies are localized adjacent to Cajal bodies and are involved in mRNA3'-end processing.


F bouton

description: Synaptic bouton found in the ventral horn of the spinal cord. F boutons range in diameter from 0.5 to 7 um and contain flattened or pleomorphic synaptic vesicles.


eisosome

description: A cell part that is composed of the eisosome membrane or MCC domain, a furrow-like plasma membrane sub-domain and associated integral transmembrane proteins, and the proteins (eisosome filaments) that form a scaffolding lattice on the cytoplasmic face. Eisosomes broadly affect overall plasma membrane organization.


description: Organized structure of distinctive morphology and function, not bounded by a lipid bilayer membrane and occurring outside the cell.


cellulosome

description: An extracellular multi-enzyme complex containing up to 11 different enzymes aligned on a non-catalytic scaffolding glycoprotein. Functions to hydrolyze cellulose.


T-tubule

description: Invagination of the plasma membrane of a muscle cell that extends inward from the cell surface around each myofibril. The ends of T-tubules make contact with the sarcoplasmic reticulum membrane.


mating projection base

description: The region where the mating projection meets the bulk of the cell, in unicellular fungi exposed to mating pheromone.


synaptic cleft

description: The narrow gap that separates the presynaptic and postsynaptic membranes, into which neurotransmitter is released.


apoplast

description: The cell membranes and intracellular regions in a plant are connected through plasmodesmata, and plants may be described as having two major compartments: the living symplast and the non-living apoplast. The apoplast is external to the plasma membrane and includes cell walls, intercellular spaces and the lumen of dead structures such as xylem vessels. Water and solutes pass freely through it.


perivitelline space

description: The space between the membrane of an oocyte and a surrounding membranous structure (zona pellucida or perivitelline membrane).


lysosomal lumen

description: The volume enclosed within the lysosomal membrane.


endolysosome lumen

description: The volume enclosed by the membrane of an endolysosome. An endolysosome is a transient hybrid organelle formed by fusion of a late endosome with a lysosome.


cytolytic granule

description: A specialized secretory lysosome that is present in cells with cytolytic capability such as cytotoxic T lymphocytes and natural killer cells. Cytolytic granules mediate the storage and regulated excretion of lytic molecules for killing of target cells.


porous cell septum

description: A septum or cross wall which does not entirely span the space between two portions of cell wall and may contain a specialized central pore structure. A porous septum allows the movement of organelles and/or cytoplasm between compartments.


dolipore septum

description: A septum, or cross-wall, between two portions of a cell or hypha; contains a central pore around which the septum is swollen to form a barrel-shaped structure; pore is covered on each side of the septum by a septal pore cap (parenthosome).


host cell synapse

description: The junction between a nerve fiber of one host neuron and another host neuron or muscle fiber or glial cell; the site of interneuronal communication.


cellular bud neck septin structure

description: Any of a series of septin structures that are localized in the bud neck of a budding fungal cell during the cell cycle.


annular furrow extracellular matrix

description: The extracellular matrix part that is a regularly spaced indentation in the outer cortical layer of the cuticle. The pattern of annular furrows corresponds to sites of invaginations in hypodermal cell membranes that, in turn, correspond to submembranous regions where actin microfilament bundles assemble early in lethargus, the first phase of the molting cycle in which activity and feeding decline.


yolk granule

description: Discrete structures that partition the water-insoluble portion of the yolk of oocytes and ova, which may or may not be membrane enclosed.


name: symbiont-containing vacuolar membrane network

description: Tubular network of extensions from the symbiont-containing vacuole membrane that protrude into the host cytoplasm.


host cell plasma membrane

description: The plasma membrane surrounding a host cell.


cis-Golgi network membrane

description: The lipid bilayer surrounding any of the compartments that make up the cis-Golgi network.


pellicle

description: The structure enclosing certain parasite cells such as certain apicomplexa and Euglenozoa; consists of the cell membrane with its associated infrastructure of microtubules, microfilaments and other organelles.


spine apparatus

description: A specialization of the endomembrane system found in some classes of dendritic spines consisting of two or more closely apposed lamellae with interspersed electron dense material. The endomembrane component is continuous with the smooth endoplasmic reticulum.


dendritic tuft

description: The terminal specialization found in some types of dendrites which consists of numerous small terminal branches, giving the dendrite a tufted appearance.


peribacteroid fluid

description: The soluble material inside the peribacteroid membrane, but outside of the bacteroid, within a bacteroid-containing symbiosome.


spindle matrix

description: A proteinaceous, nuclear-derived structure that embeds the microtubule spindle apparatus from pole to pole in a microtubule-independent manner during mitosis.


climbing fiber

description: The axon of inferior olive neuron that projects to the cerebellar cortex, largely via the inferior cerebellar peduncle. They range in diameter from 1-3 um and are myelinated until they enter the granule cell layer. They give off collaterals to the deep cerebellar nuclei. They synapse extensively with the dendrites of Purkinje cells in the molecular layer, where each fiber branches repeatedly to climb along the Purkinje cell dendritic tree. Each Purkinje cell is innervated by only a single climbing fiber.


spine synapse

description: A type of synapse occurring between an axon and a dendritic spine.


short microvillus layer

description: A layer of microvilli covering lymphocytes.


proximal convoluted tubule brush border

description: A brush border layer that is part of a proximal tubule in the kidney.


cellular bud scar

description: Crater-like ring of chitinous scar tissue located on the surface of the mother cell. It is formed after the newly emerged daughter cell separates thereby marking the site of cytokinesis and septation. The number of bud scars that accumulate on the surface of a cell is a useful determinant of replicative age.


host cell mitochondrial membrane

description: Either of the lipid bilayers that surround the host cell mitochondrion and form the host cell mitochondrial envelope.


host cell mitochondrial inner membrane

description: The inner, i.e. lumen-facing, lipid bilayer of the host cell mitochondrial envelope. It is highly folded to form cristae.


exopher

description: An extracellular vesicle that is approximately four microns in diameter, released by budding out of cells into the extracellular space, and hypothesized to be a mechanism for disposal of unwanted cellular material including protein aggregates and damaged organelles.


female germline ring canal outer rim

description: An electron opaque backbone of the insect ovarian ring canal that is a part of or adjacent to the plasma membrane. The outer rim is established as the cleavage furrow is arrested, and contains F-actin, anillin, glycoproteins and at least one a protein with a high content of phosphorylated tyrosine residues.


free sarcoplasmic reticulum membrane

description: The part of the sarcoplasmic reticulum membrane that contains calcium pumps and is devoted to calcium uptake. The free sarcoplasmic reticulum membrane consists of the longitudinal sarcoplasmic reticulum membrane and the non-junctional region of the terminal cisterna membrane.


filiform apparatus

description: A complex of cell wall invaginations in a synergid cell, similar to those in transfer cells.


endospore core

description: An intracellular part that represents the innermost portion of an endospore; the endospore core is dehydrated, enriched in dipicolinic acid and divalent cations, and metabolically inactive.


phagocytic cup lip

description: The tip or margin of the progressing circular lamella that engulfs a particle during phagocytosis. When the two lips of the cup fuse it is converted into a phagosome.


chlorosome envelope

description: The structure, composed of a monolayer of glycolipids with embedded proteins, that encloses the pigments and other contents of the chlorosome.


organelle-enclosing lipid monolayer

description: A lipid monolayer that surrounds and encloses an organelle.


microneme

description: A small, elongated secretory organelle that forms part of the apical complex, located along the main axis of an apicomplexan parasite cell within the extreme apical region and at the periphery under the inner membrane complex. Of the specialized secretory compartments identified in apicomplexans, micronemes discharge their contents first, during initial contact of the parasite's apical pole with the host cell surface. Micronemal proteins function during parasite attachment and penetration into the target cell.


mitochondrial crista

description: Any of the inward folds of the mitochondrial inner membrane. Their number, extent, and shape differ in mitochondria from different tissues and organisms. They appear to be devices for increasing the surface area of the mitochondrial inner membrane, where the enzymes of electron transport and oxidative phosphorylation are found. Their shape can vary with the respiratory state of the mitochondria.


magnetosome

description: A membrane-bound organelle that envelops particles of magnetic iron minerals in magnetotactic bacteria. Magnetosomes form linear chains that align along the cellular motility axis at midcell and function in bacterial navigation along the Earth's magnetic field. They are formed by invagination of the cell inner membrane; in some species they remain connected to the inner membrane, in others they pinch off to form independent intracellular vesicles.


dinoflagellate epicone

description: The part of a dinoflagellate cell above the cingulum; also referred to as the anterior portion of a dinoflagellate cell. It is separated from the hypocone by the cingulum.


etioplast stroma

description: The space enclosed by the double membrane of an etioplast but excluding the prothylakoid space. It contains the etioplast DNA.


mating projection

description: The projection formed by unicellular fungi in response to mating pheromone.


ascus epiplasm

description: Ascus cytoplasm that is not packaged into ascospores.


phragmosome

description: A flattened membranous vesicle containing cell wall components.


eyespot apparatus

description: A small pigmented organelle used in single-celled organisms to detect light.


C zone

description: A region of the A band in which myosin-binding protein C is located and that can be seen by electron microscopy. This is a functional zone that also includes myosin.


Gemini of coiled bodies

description: Nuclear bodies frequently found near or associated with Cajal bodies (also called coiled bodies or CBs). Gemini of coiled bodies, or 'gems', are similar in size and shape to CBs, and often indistinguishable under the microscope. Unlike CBs, gems do not contain small nuclear ribonucleoproteins (snRNPs); they contain a protein called survivor of motor neurons (SMN) whose function relates to snRNP biogenesis. Gems are believed to assist CBs in snRNP biogenesis, and to play a role in the etiology of spinal muscular atrophy (SMA).


LYSP100-associated nuclear domain

description: A nuclear body that is enriched in the lymphoid cell-specific protein LYSp100B; LANDs are globular, electron-dense structures and are morphologically distinct from the annular structures characteristic of PML bodies.


omega speckle

description: A nucleoplasmic speckle distributed in the interchromatin space of cells in close proximity to chromatin. Omega speckles are distinct from interchromatin granules and contain heterogeneous nuclear RNA-binding proteins (hnRNPs).


paraspeckles

description: Discrete subnuclear bodies in the interchromatin nucleoplasmic space, often located adjacent to nuclear specks. 10-20 paraspeckles are typically found in human cell nuclei.


nuclear dicing body

description: A small round nuclear body, measuring 0.2-0.8 microns in diameter that is diffusely distributed throughout the nucleoplasm. Several proteins known to be involved in miRNA processing have been localized to these structures. D-bodies are thought to be involved in primary-miRNA processing and/or storage/assembly of miRNA processing complexes.


interchromatin granule

description: A class of nuclear body measuring 20-25 nm in diameter and distributed throughout the interchromatin space, linked together by thin fibrils. They are believed to be storage centers for various snRNAs, snRNPs, serine/arginine-rich proteins and RNA polymerase II. A typical mammalian cell contains 25-50 clusters of interchromatin granules. Interchromatin granule clusters do not contain the heterogeneous nuclear RNA-binding proteins (hnRNPs).


sphere organelle

description: A nuclear body that is found in the germinal vesicles of amphibian oocytes, and consist of three major parts: a remarkably spherical body about 5-10 pm in diameter, smaller spherical or nearly spherical granules on the surface, and inclusions of various sizes that strongly resemble the surface granules. The parts of the sphere organelle have distinct compositions, including splicing snRNAs and proteins.


Cajal body

description: A class of nuclear body, first seen after silver staining by Ramon y Cajal in 1903, enriched in small nuclear ribonucleoproteins, and certain general RNA polymerase II transcription factors; ultrastructurally, they appear as a tangle of coiled, electron-dense threads roughly 0.5 micrometers in diameter; involved in aspects of snRNP biogenesis; the protein coilin serves as a marker for Cajal bodies. Some argue that Cajal bodies are the sites for preassembly of transcriptosomes, unitary particles involved in transcription and processing of RNA.


nuclear exosome focus

description: An nuclear body involved in nuclear mRNA surveilllance. Contains at least Mmi1, or an ortholog of it, and the nuclear exosome.


pseudopodium

description: A temporary protrusion or retractile process of a cell, associated with flowing movements of the protoplasm, and serving for locomotion and feeding.


axonemal A tubule inner sheath

description: A structural network of microtubule inner proteins (MIPs) located inside the lumen of the A tubule of the axonemal microtubule doublet that helps stabilize the A tubule.


dense fibrillar component

description: A structure found in the nucleolus, which contains newly synthesized preribosomal RNA (pre-rRNA) and a collection of proteins.


cell body fiber

description: A neuron projection that is found in unipolar neurons and corresponds to the region between the cell body and the point at which the single projection branches.


chromoplast stroma

description: The space enclosed by the double membrane of a chromoplast but excluding the photosynthetic material.


apicolateral plasma membrane

description: The apical end of the lateral plasma membrane of epithelial cells.


Golgi trans cisterna

description: The Golgi cisterna farthest from the endoplasmic reticulum; the final processing compartment through which proteins pass before exiting the Golgi apparatus; the compartment in which N-linked protein glycosylation is completed.


apical proximal dendrite

description: The dendrite of the dendritic tree, which emerges near the apical pole of a neuron, and which is the closest to the cell body of the neuron (the soma).


right anterior flagellum

description: A cilium (also called flagellum) found in Giardia species (trophozoite stage). It originates at the right anterior basal body, extends laterally through the cytoplasm, crosses the left anterior axoneme, and exits as a membrane-bound flagellum on the anterior right side of the cell.


germline ring canal

description: Germline specific intercellular bridge. During cyst formation in insects, ring canals interconnect the cells of the cyst, facilitating the passage of cytoplasmic components between cells.


female germline ring canal

description: An intercellular bridge that connects the germline cells of a female cyst.


male germline ring canal

description: An intercellular bridge that connects the germline cells of a male cyst.


vestibular calyx terminal

description: The giant, cup-shaped axon terminal of a vestibular afferent neuron, serving as a post-synaptic contact to a type I hair cell.


calyx of Held

description: The terminal specialization of a calyciferous axon which forms large synapses in the mammalian auditory central nervous system.


cone cell pedicle

description: A specialized axon terminus which is produced by retinal cone cells. Pedicles are large, conical, flat end-feet (8-10 micrometers diameter) of the retinal cone axon that lie more or less side by side on the same plane at the outer edge of the outer plexiform layer (OPL).


Herring body

description: The dilated terminal portions of neurosecretory axons constituting the hypothalamohypophyseal tract, found in close proximity to sinusoidal capillaries in the posterior pituitary. Herring bodies consist of aggregates of membrane-bound neurosecretory vesicles where oxytocin or antidiuretic hormone (ADH) are stored prior to release. Each Herring body also contains ATP and either neurophysin I or neurophysin II which bind to oxytocin and ADH, respectively.


nuclear envelope lumen

description: The region between the two lipid bilayers of the nuclear envelope; 20-40 nm wide.


P2 peroxisome

description: A subform of peroxisome that corresponds to an intermediate in a peroxisome assembly pathway, which operates by conversion of peroxisomal subforms in the direction P1, P2 -> P3 -> P4 -> P5 -> P6. P2 peroxisomes are distinguished from the other subforms on the bases of buoyant density and protein content; they are the least dense of the subforms observed.


oral apparatus

description: Complex basket- or funnel-like structure used by the cell to collect food and channel it to the cytostome; includes specialized sub-structures made up of closely-spaced cilia and underlying basal bodies and fibrillar systems.


uropod membrane

description: The portion of the plasma membrane surrounding a uropod.


cell trailing edge membrane

description: The portion of the plasma membrane surrounding the trailing edge of a motile cell.


procentriole

description: A cellular structure that is the site of a developing centriole, which will become a microtubule organizing center. During the canonical pathway of centriole duplication that occurs during the cell division cycle, procentrioles grow at the proximal ends of both mother and daughter centrioles. In the newly divided cells, the original mother and daughter centrioles become mother centrioles while the procentrioles become the new daughter centrioles. Procentrioles can also arise from de novo pathways that occur in multiciliated cells. In ciliated epithelial cells, numerous procentrioles arise form electron dense material referred to as fibrous granules and deuterosomes. The pathway of procentriole formation in multiciliated protists appears to be similar to that in mammalian multiciliated epithelium. In sperm of primitive land plants, multiple procentrioles are formed from a blepharoplast giving rise to multicilated sperm cells.


storage vacuole

description: A vacuole that functions primarily in the storage of materials, including nutrients, pigments, waste products, and small molecules.


fungal-type vacuole

description: A vacuole that has both lytic and storage functions. The fungal vacuole is a large, membrane-bounded organelle that functions as a reservoir for the storage of small molecules (including polyphosphate, amino acids, several divalent cations (e.g. calcium), other ions, and other small molecules) as well as being the primary compartment for degradation. It is an acidic compartment, containing an ensemble of acid hydrolases. At least in S. cerevisiae, there are indications that the morphology of the vacuole is variable and correlated with the cell cycle, with logarithmically growing cells having a multilobed, reticulated vacuole, while stationary phase cells contain a single large structure.


reservosome

description: A large membrane-bound endocytic organelle present only in members of the Schizotrypanum subgenus of the Trypanosoma genus and is defined as the site of storage of endocytosed macromolecules and lysosomal enzymes. It is found at the posterior end of epimastigote forms of Trypanosoma cruzi, but absent in amastigotes and trypomastigotes.


terminal cisterna

description: The portion of sarcoplasmic reticulum devoted to calcium ion storage and calcium ion release.


stigma papilla

description: A plant cell papilla that is part of a stigma papilla cell.


apical lamina of hyaline layer

description: A fibrous network that is part of the hyalin layer extracellular matrix. The apical lamina is thought to be principally composed of the glycoproteins fibropellins. This matrix has been found in echinoderms.


extracellular exosome

description: A vesicle that is released into the extracellular region by fusion of the limiting endosomal membrane of a multivesicular body with the plasma membrane. Extracellular exosomes, also simply called exosomes, have a diameter of about 40-100 nm.


reservosome membrane

description: The lipid bilayer surrounding a reservosome.


left ventral flagellum

description: A cilium (also called flagellum) found in Giardia species (trophozoite stage). It is nucleated by the left ventral basal body and exits the cell body proximally and dorsal to the ventral disc.


microspike

description: A dynamic, actin-rich projection extending from the surface of a migrating animal cell.


growth cone lamellipodium

description: A thin sheetlike process extended by the leading edge of an axonal or dendritic growth cone; contains a dense meshwork of actin filaments.


basal dendrite

description: A dendrite that emerges near the basal pole of a neuron. In bipolar neurons, basal dendrites are either on the same side of the soma as the axon, or project toward the axon.


C-fiber

description: The axon of a dorsal root ganglion cell that are responsive to pain and temperature. C-fibers are small in diameter (0.2-1.5 um) and unmyelinated.


distal dendrite

description: The dendrite of the dendritic tree that is farthest away from the neuronal cell body (the soma).


proximal dendrite

description: The dendrite of the dendritic tree that is closest to the neuronal cell body (the soma).


rod spherule

description: A specialized neuron projection which is the site of synaptic transmission produced by retinal rod cells. Rod spherules are small round enlargements of the axon (3-5 micrometers diameter) or even extensions of the cell body.


right posteriolateral flagellum

description: A cilium (also called flagellum) found in Giardia species (trophozoite stage). It is nucleated by the right posteriolateral basal body and extends cytoplasmically toward the cell posterior, marking the right anterior boundary of the lateral shield and the right lateral region of the funis before exiting at the right lateral region of the cell body.


hippocampal mossy fiber

description: An axon of a hippocampal granule cell, including dentate gyrus granule cell and CA3 granule cell, characterized by expansions (mossy fiber expansions) giving the fibers a mossy appearance. These unmyelinated axons were first described by Ramon y Cajal.


CA3 pyramidal cell dendrite

description: A dendrite of a hippocampal CA3 pyramidal cell.


axonal spine

description: A spine that originates from the axon, usually from the initial segment.


giant axon

description: Extremely large, unmyelinated axon found in invertebrates. Has high conduction speeds and is usually involved in panic or escape responses.


dendritic cell dendrite

description: A branched cellular projection (or cytoplasmic extension) that is extended from the surface of a dendritic immune cell, and which enables the cell to sample luminal pathogens and increase the surface area for antigen presentation to T cells.


rod telodendria

description: Rod telodendria are projections that originate from the rod pedicle and form gap junctions with other photoreceptors within the outer plexiform layer of the retina.


growth cone filopodium

description: A thin, stiff protrusion extended by the leading edge of an axonal or dendritic growth cone.


accessory outer segment

description: A cilium-like cell projection emanating from the inner segment and running alongside the outer segment of photoreceptors.


9+0 motile cilium

description: A motile cilium where the axoneme has a ring of nine outer microtubule doublets but no central microtubules (and is therefore called a 9+0 axoneme).


cone telodendria

description: Cone telodendria are projections that originate from the cone pedicle and form gap junctions with other photoreceptors within the outer plexiform layer of the retina.


muscle cell projection

description: A prolongation or process extending from a muscle cell. A muscle cell is a mature contractile cell, commonly known as a myocyte. This cell has as part of its cytoplasm myofibrils organized in various patterns.


cytoneme

description: A long, thin, polarized cell projection that contains actin and can extend for distances many times the diameter of the cell. Cytonemes represent extensions of cell cytoplasm and typically have a diameter of approximately 0.2um.


right ventral flagellum

description: A cilium (also called flagellum) found in Giardia species (trophozoite stage). It is nucleated by the right ventral basal body and exits the cell body proximally and dorsal to the ventral disc.


pollen tube

description: A tubular cell projection that is part of a pollen tube cell and extends from a pollen grain.


macropinocytic cup

description: A cell projection that forms at the site of macropinocytosis, a form of endocytosis that results in the uptake of relatively large amounts of extracellular fluid. The macropinocytic cup membrane selectively excludes certain proteins, such as H36 or PM4C4 in Dictyostelium, and the underlying cytoskeleton is enriched in F-actin and coronin.


right caudal flagellum

description: A cilium (also called flagellum) found in Giardia species (trophozoite stage). It is nucleated by the right caudal basal body, extending cytoplasmically and exiting at the posterior end of the cell body.


primary dendrite

description: A dendrite emerging from the cell body (the soma) of a neuron.


parallel fiber

description: A parallel fiber results from the bifurcation of a cerebellar granule cell axon in the molecular layer into two diametrically opposed branches, that are oriented parallel to the long axis of the folium.


neuron spine

description: A small membranous protrusion, often ending in a bulbous head and attached to the neuron by a narrow stalk or neck.


left anterior flagellum

description: A cilium (also called flagellum) found in Giardia species (trophozoite stage). It originates at the left anterior basal body, extends laterally through the cytoplasm, crosses the right anterior axoneme, and exits as a membrane-bound flagellum on the anterior left side of the cell.