Structure and expression of an ovine endometrial oxytocin receptor cDNA.
A sheep endometrial oxytocin receptor (OTR) cDNA (1.5 kb) was isolated from a lambda-ZAP library using a reverse transcription-PCR product probe generated from oestrous endometrial mRNA. The sheep OTR cDNA shared an overall similarity of 82% with human OTR cDNA, 85% with pig OTR cDNA and 76% with rat OTR cDNA. The encoded receptor was a 391 amino acid polypeptide 94% similar to human OTR, 94% similar to pig OTR and 93% similar to rat OTR. The sheep OTR contained two additional amino acids compared with human OTR which were located in the highly GC-rich third intracytoplasmic loop. This region is thought to be associated with G protein coupling and signal transduction. Expression of the cDNA in Cos-7 cells and measurement of oxytocin-induced phosphoinositide turnover confirmed that it coded for a functional product. The affinity of the expressed receptor was comparable with that observed for the in vivo receptor.
Riley
P R
PR
Institute of Zoology, Regents Park, London, UK.
Flint
A P
AP
Abayasekara
D R
DR
Stewart
H J
HJ
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002522:Chlorocebus aethiops; D017931:DNA Primers; D018076:DNA, Complementary; D004717:Endometrium / Q000378:metabolism*; D004971:Estrus; D005260:Female; D015870:Gene Expression; D015723:Gene Library; D006801:Humans; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D018045:Receptors, Oxytocin / Q000096:biosynthesis* / Q000235:genetics*; D011994:Recombinant Proteins / Q000096:biosynthesis; D017386:Sequence Homology, Amino Acid; D012756:Sheep; D013045:Species Specificity; D013552:Swine; D014162:Transfection
D017931:DNA Primers; D018076:DNA, Complementary; D015345:Oligonucleotide Probes; D012333:RNA, Messenger; D018045:Receptors, Oxytocin; D011994:Recombinant Proteins