SUN family
sun family
SUN proteins are type-II transmembrane proteins with nuclear-oriented N-termini and lumenal C-termini. Named for SUN domain family members (Sad1p, Unc-84) they all share a conserved SUN domain at the C-terminus of the lumenal domain. This lumenal region of SUN proteins also includes an extended coiled-coil domain. The nucleoplasmic domain of SUN proteins is structurally less characterized, but at least in some mammalian family members, has been shown to be capable of nuclear localization independent of the rest of the protein.