title: Cloning and functional characterization of a gonadal luteinizing hormone receptor complementary DNA from the African catfish (Clarias gariepinus).
abstract: A cDNA encoding a putative African catfish (Clarias gariepinus) gonadal LH receptor (cfLH-R) has been cloned. Multiple sequence alignment of the deduced amino acid sequence revealed that the cfLH-R had the highest identity with vertebrate LH receptors (>50%). Overall sequence identity between the cfLH-R and the African catfish FSH receptor (cfFSH-R) is 47%. Sequence analysis of part of the cfLH-R gene revealed the presence of an intron typically found in other vertebrate LH-R genes. Abundant cfLH-R mRNA expression was detected in ovary and testis as well as in head-kidney (the adrenal homologue in fish). Other tissues, such as muscle, brain, cerebellum, stomach, heart, and seminal vesicles, also contained detectable cfLH-R mRNA. Transient expression of the cfLH-R in HEK-T 293 cells resulted in significantly increased basal cAMP levels in the absence of gonadotropic hormone. The cAMP levels could be further elevated in response to catfish LH, salmon LH, human LH, human choriogonadotropin, and human FSH. Salmon FSH and human TSH, however, were inactive. We conclude that we have cloned a cDNA encoding the LH-R of the African catfish. This receptor displays constitutive activity but is still responsive to additional ligand-induced activation.
authors.affiliation: Faculty of Biology, Research Group Endocrinology, Utrecht University, NL-3584 CH Utrecht, The Netherlands.
authors.forename: H F
authors.initials: HF
authors.lastname: Vischer
authors.forename: J
authors.initials: J
authors.lastname: Bogerd
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002397:Catfishes / Q000235:genetics* / Q000378:metabolism; D002460:Cell Line; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D003001:Cloning, Molecular; D000242:Cyclic AMP / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D007986:Luteinizing Hormone / Q000494:pharmacology; D008297:Male; D008969:Molecular Sequence Data; D010053:Ovary / Q000378:metabolism; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011974:Receptors, LH / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013737:Testis / Q000187:drug effects / Q000378:metabolism; D014018:Tissue Distribution; D014162:Transfection
chemical_list: D006063:Chorionic Gonadotropin; D018076:DNA, Complementary; D012333:RNA, Messenger; D011974:Receptors, LH; D011994:Recombinant Proteins; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D000242:Cyclic AMP