title: Effects of short photoperiod on the expression of smad2 and smad3 mRNA in Syrian hamster testis.
abstract: The testicular localization and expression of Smad2 and Smad3 mRNA involved in the intracellular signal transduction of activin, inhibin and transforming growth factor-beta (TGF-beta) were examined under the influence of long and short photoperiod in Syrian hamsters (Mesocricetus auratus). In situ hybridization detected both Smad2 and Smad3 mRNA in spermatogonia and premeiotic spermatocytes in the active testis exposed to a long photoperiod, as well as in the regressed testis exposed to a short photoperiod. Northern blots showed that Smad2 mRNA was expressed at all stages over long and short photoperiods, whereas Smad3 mRNA was expressed at high levels in the photoperiod-induced regressed testis. The photoperiodic condition would change the balance between Smad2 and Smad3 transcripts in the testis. Thus, intracellular Smad2 and Smad3 might participate in transducing signals from activin, inhibin and TGF-beta in spermatogenetic cells.
authors.affiliation: Department of Veterinary Anatomy, Faculty of Agriculture, Iwate University, Morioka, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kano
authors.forename: M
authors.initials: M
authors.lastname: Kurohmaru
authors.forename: Y
authors.initials: Y
authors.lastname: Hayashi
authors.forename: K
authors.initials: K
authors.lastname: Taniguchi
mesh_terms: D000818:Animals; D006224:Cricetinae; D004268:DNA-Binding Proteins / Q000235:genetics*; D005786:Gene Expression Regulation / Q000502:physiology*; D017403:In Situ Hybridization; D008297:Male; D008647:Mesocricetus; D017440:Photoperiod; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics; D015398:Signal Transduction; D051899:Smad2 Protein; D051900:Smad3 Protein; D013091:Spermatogenesis; D013737:Testis / Q000502:physiology*; D013997:Time Factors; D015534:Trans-Activators / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D004268:DNA-Binding Proteins; D012333:RNA, Messenger; D051899:Smad2 Protein; D051900:Smad3 Protein; D015534:Trans-Activators