Inhibition of 80 kDa protein phosphorylation by short-wavelength UV light in NIH 3T3 cells.
The exposure of NIH 3T3 fibroblast cells to 254 nm UV radiation resulted in a temporary depression of DNA synthesis and inhibition of 80 kDa protein phosphorylation. This inhibition of protein phosphorylation was correlated with decreased protein kinase C activity in the membrane fractions of UV-damaged cells. The inositol triphosphate contents measured, by the competitive binding assay using bovine adrenal binding protein, showed 80% reduction in the fibroblasts treated with 15 J/m2 of UV light. The intracellular diacylglycerol concentration was also markedly reduced in UV-damaged cells. The results suggest that UV light causes acute reductions of inositol triphosphate and diacylglycerol contents in cells along with decreases in membrane protein kinase C activity, which leads to the inhibition of phosphorylation of an acidic protein of 80 kDa.
Shin
I
I
Department of Life Science, KAIST, Taejon, Korea.
Yoon
Y S
YS
Kang
K
K
Park
S D
SD
Joe
C O
CO
D016475:3T3 Cells; D000818:Animals; D004075:Diglycerides / Q000378:metabolism; D004307:Dose-Response Relationship, Radiation; D015180:Electrophoresis, Gel, Two-Dimensional; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D007700:Kinetics; D051379:Mice; D010750:Phosphoproteins / Q000302:isolation & purification / Q000528:radiation effects*; D011493:Protein Kinase C / Q000378:metabolism / Q000528:radiation effects; D011506:Proteins / Q000378:metabolism* / Q000528:radiation effects; D013936:Thymidine / Q000378:metabolism; D014466:Ultraviolet Rays
D004075:Diglycerides; D010750:Phosphoproteins; D011506:Proteins; D015544:Inositol 1,4,5-Trisphosphate; D011493:Protein Kinase C; D013936:Thymidine