B-cell receptor-associated protein 31 (BAP31)

B-cell receptor-associated protein 31 (BAP31, also known as BCAP31) is a ubiquitously expressed, multi-pass transmembrane protein predominantly located in the membrane of the endoplasmic reticulum (ER)[1][2][3]. Functioning both as a broad-specificity membrane protein chaperone and a quality control factor, BAP31 plays crucial roles in exporting properly folded membrane proteins from the ER to the Golgi, identifying abnormally folded proteins for ER-associated degradation, and acting as a tether and regulatory hub at mitochondria-associated membranes (MAMs)[1][2][3]. It regulates various cellular processes including autophagy, apoptosis (mediating both anti-apoptotic and pro-apoptotic functions depending on its cleavage state), ER and mitochondrial homeostasis, and immune response[1][2][3]. Loss-of-function mutations in BAP31 are linked to severe X-linked neurological disorders such as deafness, dystonia, and central hypomyelination syndrome (DDCH) as well as broader roles in cancer, metabolic disease, and viral pathogenesis[1][2][3].

Other names

BCAP31DXS1357ECDM9