The Bax-inhibitor-1 region of the receptor molecules is conserved from bacteria to humans.

1: Bax inhibitor-1 is overexpressed in prostate cancer and its specific down-regulation by RNA interference leads to cell death in human prostate carcinoma cells. Grzmil M, Thelen P, Hemmerlein B, Schweyer S, Voigt S, Mury D, Burfeind P; Am J Pathol. 2003;163:543-552. PMID:12875974

2: Comparative genomics and function analysis on BI1 family. Zhou J, Zhu T, Hu C, Li H, Chen G, Xu G, Wang S, Zhou J, Ma D; Comput Biol Chem. 2008;32:159-162. PMID:18440869