Prostaglandin F(2alpha) stimulates tyrosine phosphorylation of phospholipase C-gamma1.
In this study, we investigated the ability of prostaglandin F(2alpha) (PGF(2alpha)) to induce tyrosine phosphorylation of phospholipase C-gamma1 (PLC-gamma1) in cat iris sphincter smooth muscle (CISM) cells. PGF(2alpha)(1 microM) stimulated PLC-gamma1 tyrosine phosphorylation in a time- and dose-dependent manner with a maximum increase of 3-fold at 0.5min. The protein tyrosine kinase inhibitors, genistein, and tyrphostin A-25, blocked the stimulatory effects of PGF(2alpha), suggesting involvement of protein tyrosine kinase activity in the physiological actions of the PGF(2alpha). Furthermore, PGF(2alpha)-induced p42/p44 MAP kinase activation was also completely blocked by protein tyrosine kinase inhibitors. In summary, these findings show that PGF(2alpha) stimulates tyrosine phosphorylation of PLC-gamma1 in CISM cells and indicate that PGF(2alpha)-stimulated tyrosine phosphorylation is responsible for an early signal transduction event.
Husain
Shahid
S
Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta, GA 30912, USA. shusain@mail.mcg.edu
Jafri
Farahdiba
F
D000818:Animals; D015153:Blotting, Western; D002415:Cats; D002478:Cells, Cultured; D015237:Dinoprost / Q000235:genetics* / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D019833:Genistein / Q000494:pharmacology; D007498:Iris / Q000378:metabolism; D007527:Isoenzymes / Q000378:metabolism*; D007700:Kinetics; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009130:Muscle, Smooth / Q000166:cytology; D051966:Phospholipase C gamma; D010766:Phosphorylation; D011233:Precipitin Tests; D011485:Protein Binding; D015398:Signal Transduction; D013997:Time Factors; D010738:Type C Phospholipases / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism*; D020032:Tyrphostins / Q000494:pharmacology
D004791:Enzyme Inhibitors; D007527:Isoenzymes; D020032:Tyrphostins; C079836:tyrphostin 25; D014443:Tyrosine; D015237:Dinoprost; D019833:Genistein; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D010738:Type C Phospholipases; D051966:Phospholipase C gamma