Cloning and functional characterization of a testicular TSH receptor cDNA from the African catfish (Clarias gariepinus).
A cDNA encoding a putative thyroid-stimulating hormone receptor (cfTSH-R) was cloned from the testis of the African catfish (Clarias gariepinus). The cfTSH-R showed the highest amino acid sequence identity with the TSH-Rs of other fish species. In addition, an insertion of approximately 50 amino acids, specific for the TSH-R subfamily, was also present in the carboxy terminus of the amino-terminal extracellular domain of the cfTSH-R. Next to the testis and thyroid follicles, abundant cfTSH-R expression was detected in cerebellum, brain, ovary, seminal vesicles and pituitary, while weaker expression was found in muscle, stomach, intestine, head-kidney, liver, kidney and heart. HEK-T 293 cells, transiently expressing the cfTSH-R, significantly increased intracellular cAMP levels in response to human TSH. Catfish LH, human choriogonadotropin and human FSH were also able to induce this cfTSH-R-mediated response, although with considerably lower efficiency than human TSH. These results indicated that a functional cfTSH-R had been cloned from the testis of African catfish.
Vischer
H F
HF
Department of Endocrinology, Faculty of Biology, Hugo R Kruyt building, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
Bogerd
J
J
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002397:Catfishes / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny; D012333:RNA, Messenger / Q000378:metabolism; D011989:Receptors, Thyrotropin / Q000145:classification / Q000235:genetics* / Q000378:metabolism*; D016415:Sequence Alignment; D013737:Testis / Q000378:metabolism*; D014018:Tissue Distribution
D018076:DNA, Complementary; D012333:RNA, Messenger; D011989:Receptors, Thyrotropin