Enables endoribonuclease inhibitor activity and ubiquitin protein ligase binding activity. Involved in several processes, including negative regulation of RNA metabolic process; negative regulation of intrinsic apoptotic signaling pathway; and response to L-glutamate. Acts upstream of or within negative regulation of calcium ion transport into cytosol. Located in endoplasmic reticulum membrane and mitochondrial membrane. Biomarker of cervical squamous cell carcinoma and prostate carcinoma. [provided by Alliance of Genome Resources, Apr 2022]