Murine Bv8 gene maps near a synteny breakpoint of mouse chromosome 6 and human 3p21.

The genomic structure of the murine Bv8 gene was determined in 129/SvJ mouse, and the chromosomal localization was identified. Bv8 has first been characterized from skin secretion of the yellow-bellied toad, Bombina variegata. When injected into rat brain, this polypetide causes hyperalgesia. The murine Bv8 gene was shown to consist of four exons and was localized on chromosome 6 between the microsatellite markers D6Mit66 and D6Mit36 near the gene mem1, whereas the human counterpart was assigned to the non-syntenic region 3p21.1. Furthermore, the primary Bv8 transcript appeared to be alternatively spliced. The first variant contained all four exons yielding a product with a stretch highly enriched in basic amino acids in its central part. This domain is absent in the peptides from frog as well as in a splice variant expressed in mouse testis. A third variant gives rise to a truncated polypeptide.