The function of BFAR (bifunctional apoptosis regulator, ENSG00000103429) is as follows. Membrane-bound E3 ubiquitin ligase that plays a role in several processes including apoptosis regulation or reticulum endoplasmic stress (PubMed:14502241, PubMed:21068390). Has anti- apoptotic activity, both for apoptosis triggered via death-receptors and via mitochondrial factors (PubMed:14502241). Contributes to the dynamic control of IRE1/ERN1 signaling during ER stress by inducing BAX inhibitor 1/TMBIM6 proteasomal degradation (PubMed:21068390). Promotes the activation of TGF-beta signaling by mediating the 'Lys-63'-linked ubiquitination of TGFBR1 which is critical to activate the pathway (PubMed:33914044). Together with NGFR, negatively regulates NF-kappa-B and JNK-related signaling pathways (PubMed:22566094). Promotes the proteasome-mediated degradation of PNPLA3, a protein involveld in lipid metabolism (PubMed:38294943). {ECO:0000269|PubMed:14502241, ECO:0000269|PubMed:21068390, ECO:0000269|PubMed:22566094, ECO:0000269|PubMed:33914044, ECO:0000269|PubMed:38294943}.