Human bradykinin B2 receptor: nucleotide sequence analysis and assignment to chromosome 14.

Functional cDNA clones for human bradykinin B2 receptor were isolated from uterus RNA by a polymerase chain reaction (PCR)-based method and by screening a human cosmid library with rat bradykinin B2 receptor probe. We isolated several overlapping clones from the cosmid library, each of which encodes the entire protein coding sequence. The human bradykinin B2 receptor gene codes for a 364-amino-acid protein with a molecular mass of 41,442 Da that is highly homologous to rat bradykinin B2 receptor cDNA (81%). The entire human cDNA sequence was cloned into an expression vector and mRNA was synthesised by in vitro transcription. Applications of bradykinin caused membrane current responses in Xenopus oocytes injected with the in vitro-synthesized mRNA. Preincubation with the potent B2 antagonist, HOE140, prevented this response. The genomic clone is intronless, and we have identified an upstream promoter region and a downstream polyadenylation signal. The human bradykinin B2 receptor gene has been mapped to chromosome 14 using PCR to specifically amplify DNA from somatic cell hybrids.