Molecular cloning and tissue expression of the gonadotrophin-releasing hormone receptor in the tammar wallaby (Macropus eugenii).
Gonadotrophin-releasing hormone (GnRH) plays a pivotal role in the endocrine control of both reproduction and embryonic development. This first study of the marsupial GnRH receptor (GnRH-R) gene in the tammar wallaby provides information on the complex molecular events that regulate hypothalamic-pituitary-gonadal function in marsupials, and allows a comparison with eutherian mammals. Two identical wallaby GnRH-R cDNA clones were obtained, one isolated from cDNA generated from the testis of a 79-day-old pouch young and the other from the pituitary of an adult. Wallaby GnRH-R is composed of 328 amino acid residues. Sequence analysis showed that wallaby GnRH-R contains 7 transmembrane domains and is a member of the G protein-coupled receptor family. A putative protein kinase A phosphorylation site and a putative protein kinase C (PKC) phosphorylation site were found in the first intracellular loop, and an additional PKC phosphorylation site was located in the third intracellular loop. Comparisons with the eutherian GnRH-Rs show a greater diversity in the N-terminal extracellular domain. Wallaby GnRH-R has approximately 80% amino acid sequence homology with eutherian GnRH-Rs and 93% homology with the brush-tail possum, another member of the Diprotodontia semiorder.
Cheung
Timothy C
TC
Developmental Biology Research Group, Research School of Biological Sciences, The Australian National University, Canberra, ACT. cheung@rsbs.anu.edu.au
Hearn
John P
JP
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D016384:Consensus Sequence; D018076:DNA, Complementary / Q000737:chemistry / Q000302:isolation & purification; D005260:Female; D015870:Gene Expression; D007614:Macropodidae / Q000235:genetics*; D008297:Male; D008969:Molecular Sequence Data; D010053:Ovary / Q000737:chemistry; D010766:Phosphorylation; D010902:Pituitary Gland / Q000737:chemistry; D012333:RNA, Messenger / Q000032:analysis; D011966:Receptors, LHRH / Q000737:chemistry / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D013737:Testis / Q000737:chemistry; D014018:Tissue Distribution
D018076:DNA, Complementary; D012333:RNA, Messenger; D011966:Receptors, LHRH