Description_x000D_ General description_x000D_ Inositol-requiring enzyme-1 (IRE1), consists of an N-terminal endoplasmic reticulum (ER) luminal domain, a transmembrane domain, and a C-terminal cytoplasmic region composed of a Ser/Thr protein kinase domain and a site-specific endoribonuclease (RNase) domain._x000D_ The gene ERN1 (endoplasmic reticulum to nucleus signaling 1) encodes an ER transmembrane kinase/endoribonuclease that is also referred to as IRE1α (inositol-requiring transmembrane kinase and endonuclease 1α). The serine-threonine protein kinase encoded by this gene is ubiquitously expressed in cells and tissues._x000D_ Application_x000D_ Anti-IRE1α antibody produced in rabbit has been used in western blotting and immunoprecipitation._x000D_ Physical form_x000D_ Solution in 0.01 M phosphate buffered saline, pH 7.4, containing 15 mM sodium azide._x000D_ Disclaimer_x000D_ Unless otherwise stated in our catalog or other company documentation accompanying the product(s), our products are intended for research use only and are not to be used for any other purpose, which includes but is not limited to, unauthorized commercial uses, in vitro diagnostic uses, ex vivo or in vivo therapeutic uses or any type of consumption or application to humans or animals._x000D_ Biochem/physiol Actions_x000D_ ER transmembrane kinase/endoribonuclease serves as an ER stress sensor that initiates the splicing of the mRNA encoding X-box–binding protein 1 (XBP-1) upon activation. Spliced XBP-1 mRNA produces homeostatic transcription factor XBP1. Under ER stress, the RNase activity of IRE1α cleaves many ER-localized mRNAs associated with apoptosis. The cytosolic motif of the activated form of IRE1α associates with the adaptor protein TRAF2 (tumor necrosis factor (TNF)–associated factor 2). This complex activates the c-Jun N-terminal kinase (JNK) signaling pathway._x000D_ Inositol-requiring enzyme-1 (IRE1) is involved in the unfolded protein response (UPR), a transcriptional program induced by endoplasmic reticulum (ER) stress. The endonuclease activity of IRE1 autoregulates its mRNA and is required for the UPR. IRE1 senses the status of luminal protein folding in the ER via its N-terminal luminal domain. Presence of unfolded and misfolded proteins leads to dimerization, trans-autophosphorylation and activation of IRE1.