HRI Rabbit Polyclonal Antibody

The protein encoded by this gene acts at the level of translation initiation to downregulate protein synthesis in response to stress. The encoded protein is a kinase that can be inactivated by hemin. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Aug 2008], catalytic activity:ATP + a protein = ADP + a phosphoprotein., enzyme regulation:Hemin inactivates EIF2AK1 by promoting the formation of a disulfide-linked homodimer. Binding of nitric oxide (NO) to the heme iron in the N-terminal heme-binding domain activates the kinase activity, while binding of carbon monoxide (CO) suppresses kinase activity., function:Mediates down-regulation of protein synthesis in response to various stress conditions by the phosphorylation of EIF2S1 at 'Ser-48' and 'Ser-51'. Protein synthesis is inhibited at the level of initiation., miscellaneous:Can bind 2 molecules of heme per polypeptide chain., PTM:Activated by autophosphorylation; phosphorylated predominantly on serine and threonine residues, but also on tyrosine residues., similarity:Belongs to the protein kinase superfamily., similarity:Belongs to the protein kinase superfamily. Ser/Thr protein kinase family. GCN2 subfamily., similarity:Contains 1 protein kinase domain., similarity:Contains 2 HRM (heme regulatory motif) repeats., subunit:Synthesized in an inactive form that binds to the N-terminal domain of CDC37. Has to be associated with a multiprotein complex containing Hsp90, CDC37 and PPP5C for maturation and activation by autophosphorylation. The phosphatase PPP5C modulates this activation. Homodimer; non-covalently bound in the absence of hemin. Converted to an inactive disulfide linked homodimer in the presence of hemin., tissue specificity:Detected in heart, brain, placenta, lung, liver, skeletal muscle, pancreas, kidney, spleen, muscle and stomach.

EIF2AK1; HRI; KIAA1369; Eukaryotic translation initiation factor 2-alpha kinase 1; Heme-controlled repressor; HCR; Heme-regulated eukaryotic initiation factor eIF-2-alpha kinase; Heme-regulated inhibitor; Hemin-sensitive initiation factor 2