Endoplasmic Reticulum to Nucleus Signalling 1 (ERN1) Antibody – Rabbit Polyclonal

The protein encoded by this gene is the ER to nucleus signalling 1 protein, a human homologue of the yeast Ire1 gene product. This protein possesses intrinsic kinase activity and an endoribonuclease activity and it is important in altering gene expression as a response to endoplasmic reticulum-based stress signals. [provided by RefSeq, Jul 2008]

IRE1: a ser/thr protein kinase that possess endonuclease activity. Important in altering gene expression as a response to endoplasmic reticulum based stress signals. Senses unfolded proteins in the lumen of the endoplasmic reticulum via its N-terminal domain, which leads to enzyme auto-activation. The active endoribonuclease domain splices XBP1 mRNA to generate a new C-terminus, converting it into a potent unfolded-protein response transcriptional activator and triggering growth arrest and apoptosis. The kinase domain is activated by trans-autophosphorylation. Kinase activity is required for activation of the endoribonuclease domain. Ubiquitously expressed. High levels observed in pancreatic tissue. Functionally connected with insulin biosynthesis in pancreatic beta cells. Homodimer; disulfide-linked. Dimer formation is driven by hydrophobic interactions within the N-terminal luminal domains and stabilized by disulfide bridges. Also binds HSPA5, a negative regulator of the unfolded protein response. This interaction may disrupt homodimerization and prevent activation of IRE1.

Protein type: Apoptosis; Chaperone; EC 2.7.11.1; Endoplasmic reticulum; IRE family; Kinase, protein; Membrane protein, integral; Other group; Protein kinase, Other; Protein kinase, Ser/Thr (non-receptor); Ribonuclease

Chromosomal Location of Human Ortholog: 17q23.3

Cellular Component: cytoplasm; endoplasmic reticulum; endoplasmic reticulum membrane; integral to endoplasmic reticulum membrane

Molecular Function: ADP binding; ATP binding; endoribonuclease activity; enzyme binding; Hsp70 protein binding; Hsp90 protein binding; identical protein binding; magnesium ion binding; platelet-derived growth factor receptor binding; protein binding; protein homodimerization activity; protein serine/threonine kinase activity

Biological Process: activation of JNK activity; cell cycle arrest; endothelial cell proliferation; mRNA catabolic process; mRNA cleavage; positive regulation of RNA splicing; protein amino acid autophosphorylation; protein amino acid phosphorylation; regulation of macroautophagy; unfolded protein response, activation of signaling protein activity