Cellular signal transduction system in prostaglandin-stimulated osteoblast-like MC3T3-E1 cells : Phospholipid turnover and protein tyrosine phosphorylation
Project/Area Number |
06672000
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
Surgical dentistry
|
Research Institution | Gifu University |
Principal Investigator |
NAKASHIMA Shigeru Gifu University, School of Medicine, Department of Biochemistry, Lecturer, 医学部, 講師 (60188935)
|
Co-Investigator(Kenkyū-buntansha) |
OKA Nobumitsu Gifu University, School of Medicine, Department of Oral and Maxillo-facial Surge, 医学部, 教授 (80019893)
|
Project Period (FY) |
1994 – 1995
|
Project Status |
Completed (Fiscal Year 1995)
|
Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1995: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1994: ¥1,400,000 (Direct Cost: ¥1,400,000)
|
Keywords | osteoblast cells / prostaglandins / phospholipase C / phospholipase D / protein kinase C / protein tyrosine kinase / プロスタグランシン / プロスタグランジンFSα / ジアシルグリセロール / ホスファチジン酸 / Cキナーゼ / MAPキナーゼ |
Research Abstract |
The combination of beta-glycerophosphate and ascorbic acid increased alkaline phosphate (ALP) activity, a maraker for osteoblastic differentiation, in clonal osteoblast like cell line MC3T3-E1. The increase was detected as 24 hours after the addition of these agents to growth medium and reached almost maximal level at 5 days of culture. Although increase in intracellular cyclic AMP level is known to induce osteoblastic acell differentiation, these treatment did not cause significant increase in cyclic AMP.Treatment of beta-glycerophsphate and ascorbic acid suppressed activaaton of phosphoinositide-specific phospholipase C (PI-PLC) and phospholipase D (PLD) in response to prostaglandin F_<2alpha> (PGF_<2alpha>) by 20-30% and 15%, respectively. Western blot analyzes with subtype-specific PI-PLC antibodies revealed that in cells treated for 5 days with these differentiation inducers, the levels of PI-PLCbeta1 and PI-PLCbeta3 decreased to 37% and 67% compared to those of undifferentiated control cells, respectively. However, the level of PLC_<gamma>1 and those of protein kinase C isozymes (alpha, beta1, beta2, delta, epsilon, rheta, zeta) remained unaltered. PGF_<2alpha> also stimulated protein tyrosine phosphorilations and activation of mitogen-activated protein (MAP) kinases. These responses were not affected by differentiation induceres. These results suggest that the suppressed expression of PI-PLCbeta1 and PI-PLCbeta3 are closely related to osteoblast cell differentiation.
|
Report
(3 results)
Research Products
(6 results)