Cytoplasmic Polyadenylation Element Binding Protein 2 (CPEB2)

The protein encoded by this gene is highly similar to cytoplasmic polyadenylation element binding protein (CPEB), an mRNA-binding protein that regulates cytoplasmic polyadenylation of mRNA as a trans factor in oogenesis and spermatogenesis. Studies of the similar gene in mice suggested a possible role of this protein in transcriptionally inactive haploid spermatids. Alternatively spliced transcript variants encoding distinct isoforms have been described. Cpeb2 shares 75.9% and 69.3% amino acid identity with human CPEB3 and CPEB4, respectively.

Cpeb2 expression in testis only, but RT-PCR showed expression in all mouse tissues examined. In situ hybridization of mouse testis revealed Cpeb2 primarily in round spermatids of steps 1 through 7, but not in spermatogonia or spermatocytes.