Modulation of the G0 to S phase transit time by insulin: potential involvement of protein phosphorylation.
BHK fibroblasts can be growth arrested by incubation in low serum (0.1%) medium. Growth is initiated by incubating cells in high serum (10%) medium. We have found that if the quiescent cells in low serum medium are incubated with insulin, the G0 to S transit time is decreased by two to six hours when serum (10%) is added back to the culture. The effect of insulin treatment of quiescent cells on the cellular phosphoprotein profile was examined. It was found that insulin stimulated the phosphorylation of a 96,000 dalton cytosol protein. This protein is also intensely phosphorylated in proliferating cells and may be one of the critical intracellular events to occur when a cell initiates growth.
D000818:Animals; D002453:Cell Cycle / Q000187:drug effects*; D002478:Cells, Cultured; D006224:Cricetinae; D004261:DNA Replication / Q000187:drug effects; D007328:Insulin / Q000494:pharmacology*; D007700:Kinetics; D008970:Molecular Weight; D010750:Phosphoproteins / Q000378:metabolism*; D014176:Protein Biosynthesis
D007328:Insulin; D010750:Phosphoproteins