Bcl-2 Protein Family

The Bcl-2 protein family consists of proteins that contain at least one evolutionarily conserved BH domain out of the four that exist (BH1, BH2, BH3, BH4).  Within this family, there exists pro-apoptotic proteins and anti-apoptotic proteins that work together to govern the fate of the cell.  Anti-apoptotic proteins conserve all four BH domains, and include Bcl-2, Bcl-XL, Bcl-W, Mcl-1, and A1.  Pro-apoptotic proteins can be subdivided into two groups, those with multiple BH domains such as Bax and Bak, and those with only the BH3 domain such as Bid, Bim, Bad, PUMA, and NOXA.