PUBLICATION

Cloning, expression and enzyme activity analysis of testicular 11beta-hydroxysteroid dehydrogenase during seasonal cycle and after hCG induction in air-breathing catfish Clarias gariepinus

Authors
Rasheeda, M.K., Kagawa, H., Kirubagaran, R., Dutta-Gupta, A., and Senthilkumaran, B.
ID
ZDB-PUB-100317-15
Date
2010
Source
The Journal of steroid biochemistry and molecular biology   120(1): 1-10 (Journal)
Registered Authors
Keywords
11β-Hydroxysteroid dehydrogenase, 11-Ketotestosterone, Ontogeny, Testicular cycle, Spermatogenesis
MeSH Terms
  • 11-beta-Hydroxysteroid Dehydrogenase Type 2/genetics*
  • 11-beta-Hydroxysteroid Dehydrogenase Type 2/metabolism
  • Chorionic Gonadotropin/pharmacology*
  • Testis/metabolism
  • Catfishes/genetics*
  • Catfishes/metabolism
  • Seasons
  • Cloning, Molecular
  • Gene Expression Regulation, Enzymologic/drug effects*
  • Animals
  • Humans
  • Male
  • Gene Expression Regulation, Developmental/drug effects*
PubMed
20219674 Full text @ Steroid Biochem. Mol. Biol.
Abstract
A full length cDNA encoding 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) was cloned from testis of air-breathing catfish, Clarias gariepinus which showed high sequence homology to zebrafish and eel. The open reading frame of 11beta-HSD2 was then transfected to COS-7 cells, which converted 11beta-hydroxytestosterone (11-OHT) to 11-ketotestosterone (11-KT). Using NAD(+), 11beta-HSD2 from testicular microsomes oxidized 11-OHT with apparent K(m) 56+/-4nM and V(max) 55+/-6 pmol/h/mg-protein values. Tissue distribution analysis revealed prominent expression in testis, anterior kidney, liver and gills. Expression of 11beta-HSD2 in testis and serum levels of 11-KT were high in the prespawning phase. Administration of human chorionic gonadotropin (hCG) during prespawning and resting phases revealed initial rise in 11beta-HSD2 transcript at 4h followed by gradual increase at 8h, 12h and peaking at 24h, only in testis of prespawning phase. Rate of conversion of 11-OHT to 11-KT by testicular microsomes during different testicular phases and after hCG administration corroborated well with the expression of 11beta-HSD2. Ontogeny study indicated that this enzyme is expressed during testicular development. Thus the spatio-temporal expression supported with putative dehydrogenase activity and circulating 11-KT data clearly suggest a major role for 11beta-HSD2 during testicular differentiation and seasonal testicular cycle in catfish.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping