title: Dynamic expression of 11β-hydroxylase during testicular development, recrudescence and after hCG induction, in vivo and in vitro in catfish, Clarias batrachus.
abstract: Cytochrome P450 11β-hydroxylase (11β-h), is involved in the production of 11-hydroxytestosterone, an immediate precursor for 11-ketotestosterone (11-KT), a potent androgen in teleosts. To understand the role of 11β-h in gonadal development, maturation, function and recrudescence in an annually reproducing teleost, the present study was conducted using Clarias batrachus. Four forms of 11β-h cDNA, regular type (2.253 kb), variant 1 (1.290 kb), variant 2 (1.223 kb) and variant 3 (1.978 kb) were identified from the testis of catfish which expressed ubiquitously with high levels in testis. 11β-h transcripts were detected as early as 0 days post hatch further, stage- and sex-dependent increase in the 11β-h transcripts were seen during gonadal differentiation/development. In addition, high expression of 11β-h (regular type) in pre-spawning phase was detected. Corroboratively, levels of 11-KT in serum and testicular tissue was high during pre-spawning and spawning phases, which might facilitate initiation and normal progression of spermatogenesis. The expression of 11β-h was high after human chorionic gonadotropin induction in vivo (all forms), and in vitro (regular type). Immunohistochemical and immunofluorescence localization showed the presence of 11β-h in Sertoli and interstitial/Leydig cells of the testis. These results suggest that 11β-h is involved in late stages of testicular development, together with the regulation of seasonal reproductive cycle in catfish.
authors.affiliation: Laboratory of Molecular Endocrinology and Reproductive Biology, Department of Animal Biology, School of Life Sciences, University of Hyderabad, P.O. Central University, Hyderabad 500046, India.
authors.forename: Anbazhagan
authors.initials: A
authors.lastname: Rajakumar
authors.affiliation: Laboratory of Molecular Endocrinology and Reproductive Biology, Department of Animal Biology, School of Life Sciences, University of Hyderabad, P.O. Central University, Hyderabad 500046, India. Electronic address: bsksl@uohyd.ernet.in.
authors.forename: Balasubramanian
authors.initials: B
authors.lastname: Senthilkumaran
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002397:Catfishes / Q000254:growth & development* / Q000378:metabolism*; D006063:Chorionic Gonadotropin / Q000494:pharmacology*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004997:Ethinyl Estradiol / Q000494:pharmacology; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D012727:Sex Characteristics; D012733:Sex Differentiation / Q000187:drug effects; D013091:Spermatogenesis / Q000187:drug effects / Q000502:physiology; D013252:Steroid 11-beta-Hydroxylase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013737:Testis / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development*; D013739:Testosterone / Q000031:analogs & derivatives / Q000097:blood
chemical_list: D006063:Chorionic Gonadotropin; D018076:DNA, Complementary; D012333:RNA, Messenger; D013739:Testosterone; D004997:Ethinyl Estradiol; D013252:Steroid 11-beta-Hydroxylase; C003600:11-ketotestosterone
keywords: 11-KT levels; 11β-Hydroxylase; Catfish; Gonadal ontogeny; Seasonal reproductive cycle; hCG induction