Participates in tumor necrosis factor-alpha (TNF)-induced cell death (PubMed:14592447). May be a target of Wnt/beta-catenin signaling in the liver (PubMed:20538055). Interacts with BRI3BP (PubMed:11860200, PubMed:30983867). Interacts with MGAT1 and IFITM3 (PubMed:30983867). Interacts with BRI3BP, MGAT1 and IFITM3; the interactions are weaker than with isoform 1. Co-localizes with MGAT1 and IFITM3 at the perinuclear region. Diffuse localization in the cytoplasm and nucleus. Up-regulated during TNF-mediated inflammation and immunity (By similarity). Up-regulated by beta-catenin and TCF4 (PubMed:20538055). Belongs to the BRI3 family.