Differential regulation of prostaglandin endoperoxide synthase-2 transcription in ovine granulosa and large luteal cells.
The objective of the present study was to evaluate second messenger regulation of prostaglandin synthase-2 (PGS-2) mRNA and PGS-2 promoter in ovine granulosa cells and large luteal cells. In granulosa cells, PGS-2 mRNA was induced by forskolin (PKA activator) but not by phorbol didecanoate (PDD; PKC activator) with maximal stimulation at 24 h. In contrast, PDD was the more potent inducer in large luteal cells with the most dramatic effect by 4 h. Similarly, forskolin but not PDD increased media PGF2 alpha in granulosa cells at 24 h; whereas, PDD but not forskolin increased PGF2 alpha at 4 h and 24 h in large luteal cells. To evaluate if these effects were due to activation of transcription, a plasmid was constructed containing 1500 bp of PGS-2 promoter linked to a luciferase gene. Forskolin stimulated transcription from this construct in granulosa cells (5-fold); whereas, PDD but not forskolin stimulated transcription in large luteal cells (40-fold). Taking these findings together, we propose that transcriptional regulation of the PGS-2 gene changes from PKA-dependence in granulosa cells to PKC-dependence in large luteal cells after luteinization.
Wu
Y L
YL
Endocrinology-Reproductive Physiology Program, University of Wisconsin-Madison, USA.
Wiltbank
M C
MC
D000818:Animals; D005576:Colforsin / Q000494:pharmacology; D015237:Dinoprost / Q000032:analysis / Q000096:biosynthesis; D005260:Female; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006107:Granulosa Cells / Q000201:enzymology*; D007527:Isoenzymes / Q000235:genetics*; D008184:Luteal Cells / Q000201:enzymology*; D010703:Phorbol Esters / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012756:Sheep; D014158:Transcription, Genetic; D014162:Transfection
D007527:Isoenzymes; D010703:Phorbol Esters; D012333:RNA, Messenger; D005576:Colforsin; D015237:Dinoprost; D011451:Prostaglandin-Endoperoxide Synthases