IRE2/ERN2

IRE2β (ERN2), the paralog of the ubiquitously expressed IRE1α, shows a restricted expression pattern concentrated in secretory epithelia of the gut, airway and liver. Like IRE1α, it is an ER transmembrane protein with luminal sensing, kinase and RNase domains that respond to unfolded protein load and can splice XBP1 mRNA and perform RIDD, though generally with lower activity. IRE2β has been implicated in tuning mucosal secretory function, intestinal inflammation and host responses to infection, and it helps shape ER homeostasis in cells with high secretory demand. Recombinant IRE2β supports comparative studies of the two IRE1 branches of the unfolded protein response.