Stage-dependent expression of mRNA for cyclic protein 2 during spermatogenesis is modulated by elongate spermatids.
Cyclic protein 2 (CP-2) is a product of the Sertoli cell which is secreted in a cyclical manner according to the stage of the spermatogenic cycle. This study has assessed the influence of the germ cell complement on expression of CP-2 mRNA. Adult rats were treated with 650 mg/kg methoxyacetic acid (MAA) to induce the specific depletion of > 80% of pachytene and later spermatocytes from most tubules, and expression of CP-2 mRNA was then assessed at various times after treatment when particular germ cell types were depleted selectively. CP-2 mRNA was specifically localised to the Sertoli cells of the seminiferous tubules by non-radioactive in situ hybridisation using a digoxigenin-labelled riboprobe. A stage specific variation in CP-2 mRNA levels was observed, with the mRNA being most abundant at stages IV-VII of the spermatogenic cycle. Northern analysis revealed that treatment with MAA led to an apparent increase in the amount of the major 1.7 kb CP-2 transcript when either pachytene spermatocytes or round spermatids were depleted. In contrast, the level of CP-2 mRNA was decreased by more than half at 21 days after MAA treatment. This decrease was confirmed by in situ hybridisation at 21 days after MAA treatment, when CP-2 mRNA expression was found to be decreased or absent from tubules at stages at which CP-2 mRNA is normally expressed (stages IV-VII) when elongate spermatids were depleted selectively from these tubules. These observations lead us to hypothesise that elongate spermatids positively modulate CP-2 mRNA expression in the Sertoli cell.
Maguire
S M
SM
MRC Reproductive Biology Unit, Edinburgh, UK.
Millar
M R
MR
Sharpe
R M
RM
Saunders
P T
PT
D000085:Acetates / Q000494:pharmacology; D000818:Animals; D001483:Base Sequence; D056668:Cathepsin L; D002403:Cathepsins / Q000096:biosynthesis / Q000235:genetics*; D002450:Cell Communication; D003546:Cysteine Endopeptidases; D004247:DNA / Q000235:genetics; D010450:Endopeptidases; D004790:Enzyme Induction; D008297:Male; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics*; D051381:Rats; D017208:Rats, Wistar; D012708:Sertoli Cells / Q000201:enzymology*; D013087:Spermatids / Q000502:physiology*; D013090:Spermatocytes / Q000187:drug effects; D013091:Spermatogenesis; D013737:Testis / Q000187:drug effects / Q000648:ultrastructure
D000085:Acetates; D012333:RNA, Messenger; D004247:DNA; D002403:Cathepsins; D010450:Endopeptidases; D003546:Cysteine Endopeptidases; D056668:Cathepsin L; C534280:Ctsl protein, rat; C013598:methoxyacetic acid