Predicted to enable several functions, including ATP binding activity; magnesium ion binding activity; and unfolded protein binding activity. Involved in several processes, including positive regulation of JUN kinase activity; regulation of transcription, DNA-templated; and response to endoplasmic reticulum stress. Acts upstream of or within intrinsic apoptotic signaling pathway in response to endoplasmic reticulum stress. Located in endoplasmic reticulum quality control compartment. Part of IRE1-TRAF2-ASK1 complex. Is expressed in central nervous system and retina. Orthologous to human ERN2 (endoplasmic reticulum to nucleus signaling 2). [provided by Alliance of Genome Resources, Apr 2022]