Structure of the bovine follicle-stimulating hormone receptor complementary DNA and expression in bovine tissues.

We report the complementary DNA structure obtained by reverse transcription and polymerase chain reaction amplification encoding the complete amino acid sequence for the bovine follicle-stimulating hormone receptor (bFSHr). The deduced amino acid sequence for the cDNA revealed a mature polypeptide consisting of 678 amino acids (theoretical weight of 76.4 kDa) and a 17 amino acid putative leading signal peptide. The receptor consists of a large NH2-terminal extracellular membrane domain of 349 aa with 3 potential N-linked glycosylation sites, a transmembrane domain (264 aa) consisting of 7 putative membrane spanning segments, and an intracytoplasmic COOH-terminal domain (65 aa). Four potential phosphorylation sites were found in the transmembrane domain and the COOH-terminal domain. The amino acid sequence is 97%, 89%, and 88% homologous to the ovine, human, and rat FSHr respectively, with complete conservation of the 22 cysteine residues in the whole protein and the 3 N-linked glycosylation sites on the extracellular membrane domain. Northern blot analysis of total mRNA in bovine tissues revealed a major mRNA transcript of 2.55 kb for the bFSHr in the ovary without corpus luteum, and in the testis. No expression was found in other tissues analyzed. Total RNA from bovine granulosa cells collected from pregnant mare serum gonadotropin (PMSG)-treated prepubertal heifers showed 2 major mRNA transcripts of 6.8 and 2.55 kb, and 3 minor transcripts of 3.8, 3.3, and 1.6 kb. Bovine granulosa cells cultured with porcine FSH (0, 2, 10 ng/ml) for 4 days showed a decrease in the steady state level of the FSHr mRNA.(ABSTRACT TRUNCATED AT 250 WORDS)