Rabbit anti-Human Bl-1 polyclonal antibody for WB. BI-1 (Bax inhibitor 1), also designated testis enhanced gene transcript (TEGT), is a regulator of cell death pathways controlled by Bcl-2 and Bax. BI-1 is an integral membrane protein containing six membrane-spanning segments and is predominantly localized to intracellular membranes, similar to Bcl-2 family proteins. The human protein contains 237 amino acids. BI-1 can interact with Bcl-2 and Bcl-XL When overexpressed in mammalian cells, BI-1 suppresses apoptosis induced by Bax, etoposide, staurosporine and growth factor deprivation. BI-1 antisense induces apoptosis.