Cloning and characterization of zfBLP1, a Bcl-XL homologue from the zebrafish, Danio rerio

The importance of the Bcl-2 family proteins in normal vertebrate embryogene sis is being recognized; however, their regulatory mechanism is poorly unde rstood. We report here the cloning and characterization of a novel zebrafis h Bcl-2 family protein, zfBLP1. The zfBLP1 cDNA is 1942 nucleotides long, e ncoding a polypeptide of 238 amino acids. The primary sequence of zfBLP1 sh ares 50% identity to human Bcl-XL, and contains all four conserved BR domai ns of the Bcl-2 family proteins. Primary sequence analysis identified a con sensus ER retention signal at the C-terminal end of zfBLP1. Northern blot a nalysis indicated that there were two major and two minor zfBLP1 mRNA speci es expressed during embryonic development. Among the two major mRNA species , the short one, approx. 3 kb in size, was expressed throughout embryonic d evelopment, while the long one, approx. 7 kb long, was not detectable until the gastrula stage. These results suggest that zfBLP1 is a novel Bcl-2 fam ily protein under complicated regulations, and is likely to play an importa nt role in zebrafish oogenesis and embryogenesis. (C) 2001 Elsevier Science B.V. All rights reserved.