Endoplasmic reticulum to nucleus signaling family
endoplasmic reticulum to nucleus signaling family
ERN1 and ERN2 are paralogs encoding proteins with a similar overall structure, containing a luminal sensor domain, a transmembrane and juxtamembrane domain and cytoplasmic enzymatic kinase and endonuclease domains. ERN1 functions as a ubiquitous ER stress sensor and mediator of the unfolded protein response. The function of ERN2 is less clear but its expression is restricted to epithelial cells lining mucosal surfaces, such as the respiratory and gastrointestinal tracts, suggesting a role in mucosal homeostasis.