Heat Shock 27kDa Associated Protein 1 (HSPBAP1)

HSPBAP1,The deduced 488-amino acid protein has a calculated molecular mass of 53.1 kD. HSPBAP1 shares 80% identity with the rat homolog, PASS1. RT-PCR detected expression of HSPABAP1 in all tissues examined except brain. Highest expression was detected in thymus, ovary, and pancreas.

The breakpoints in both genes were intronic, and the fusion created a transcript where the first 2 exons of DIRC3 replaced exon 1 of HSPBAP1. The putative 451-amino acid truncated HSPBAP1 protein retained its JmjC and HSP27-interacting domains, which are associated with chromatin remodeling and stress response, respectively. Rat PASS1 is a novel protein binding specifically to hsp27 and thus plays a role in regulating stress response in the living cell.