Delivery of a cyclic adenosine 3',5'-monophosphate response element-binding protein (creb) mutant to seminiferous tubules results in impaired spermatogenesis.
FSH binding to Sertoli cells is required for optimal production of sperm in mammals. The cAMP response element-binding protein (CREB) is a major mediator of FSH-induced changes in gene expression. To determine whether CREB is required for spermatogenesis, an adenovirus encoding a phosphorylation-defective CREB mutant (AdCREBm1) was used to inhibit CREB activity in Sertoli cells. Addition of AdCREBm1 to primary rat Sertoli cell cultures completely abolished induction of the CREB-regulated c-fos gene. Injection of an adenovirus encoding ss-galactosidase into the rat testis seminiferous tubules in vivo demonstrated that predominately Sertoli cells were infected by adenovirus. AdCREBm1-directed expression of CREBm1 in seminiferous tubules did not affect Sertoli cell viability, but resulted in the apoptosis of meiotic spermatocyte germ cells within 4 days of adenovirus injection into seminiferous tubules. Disrupted spermatogenesis, defined by at least a 75% reduction of round spermatids, was observed in 42 +/- 5.8% of seminiferous tubules 14 days after AdCREBm1 infection, whereas using this criteria, testes injected with a control adenovirus did not display disrupted spermatogenesis. These data demonstrate that AdCREBm1 causes apoptosis and elimination of germ cells and suggest that CREB is required to produce a Sertoli cell-derived factor that is critical for germ cell survival.
Scobey
M
M
Department of Cell Biology and Physiology, University of Pittsburgh Pennsylvania 15261, USA.
Bertera
S
S
Somers
J
J
Watkins
S
S
Zeleznik
A
A
Walker
W
W
D000818:Animals; D017209:Apoptosis / Q000502:physiology; D002478:Cells, Cultured; D017362:Cyclic AMP Response Element-Binding Protein / Q000235:genetics* / Q000502:physiology*; D018014:Gene Transfer Techniques; D008297:Male; D009154:Mutation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012671:Seminiferous Tubules / Q000502:physiology*; D012708:Sertoli Cells / Q000378:metabolism; D013090:Spermatocytes / Q000502:physiology; D013091:Spermatogenesis / Q000502:physiology*; D013094:Spermatozoa / Q000378:metabolism; D014158:Transcription, Genetic / Q000502:physiology
D017362:Cyclic AMP Response Element-Binding Protein