Regulation of c-fos mRNA expression in Sertoli cells by cyclic AMP, calcium, and protein kinase C mediated pathways.
The role of second messenger pathways, cyclic AMP, calcium, and protein kinase C (PKC) in the transcriptional regulation of c-fos protooncogene expression in rat Sertoli cells was investigated. c-fos expression was monitored by Northern blot analysis. Although the action of FSH on Sertoli cells is considered to be mediated by cAMP, dibutyryl cAMP (dbcAMP), a potent membrane permeable analog of cAMP, induced much less c-fos mRNA expression than FSH ( < 50%) suggesting that additional cAMP-independent mechanisms may mediate the effect of FSH on c-fos. Specific intracellular inhibitors of PKC decreased c-fos induction in response to FSH by more than 50%. Ionomycin, which increases intracellular free calcium concentration, induced c-fos expression significantly. These data demonstrate that Sertoli cell c-fos mRNA expression is under multifactorial regulation by cAMP, calcium, and PKC.
Jia
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Department of Cell Biology, Georgetown University Medical Center, Washington, DC 20007, USA.
Ravindranath
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N
Papadopoulos
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Dym
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D000818:Animals; D015152:Blotting, Northern; D003994:Bucladesine / Q000494:pharmacology; D002118:Calcium / Q000502:physiology*; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000502:physiology*; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D016762:Genes, fos; D015759:Ionomycin / Q000494:pharmacology; D007476:Ionophores / Q000494:pharmacology; D008297:Male; D011493:Protein Kinase C / Q000502:physiology*; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D015290:Second Messenger Systems / Q000502:physiology*; D012708:Sertoli Cells / Q000187:drug effects / Q000378:metabolism*
D017362:Cyclic AMP Response Element-Binding Protein; D007476:Ionophores; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D015759:Ionomycin; D003994:Bucladesine; D000242:Cyclic AMP; D011493:Protein Kinase C; D002118:Calcium