19R-Hydroxyprostaglandins are major components of human seminal fluid. They
are apparently formed in the seminal vesicles by NADPH-dependent omega 2-h
ydroxylation. The hydroxylase is likely a cytochrome P450 (CYP), which has
not been identified. To address this issue we studied gene expression of CY
Ps in human seminal vesicles (n = 4) with reverse-transcription polymerase
chain reaction (RT-PCR). CYP1B1, CYP2E1, CYP2J2, CYP3A5, CYP4B1, and CYP4B1
with insertion of three nucleotides (Ser207) were detected in all subjects
. RT-PCR with degenerate primers for the CYP4 family yielded a novel cDNA s
equence, which was derived from a previously reported genomic sequence on c
hromosome 19p13.1 and present in all subjects. cDNA cloning showed that the
deduced amino acid sequence consisted of 520 amino acids. Northern blot an
alysis demonstrated mRNA transcripts of similar to 2.1 and similar to 2.3 k
b. The deduced protein showed 81.2 and 76.7% amino acid identity with the h
uman enzymes CYP4F2 and CYP4F3. The novel CYP was designated CYP4F8. (C) 19
99 Academic Press.