Metabolic changes in fibroblast adhesion sites induced by growth factors

The mechanisms involved in the association between membrane movements and the initiation of DNA synthesis were approached measuring the synthesis of membrane-associated substances after stimulation of resting phase cultures. The inducement of the division cycle by fresh serum, FGF and a growth factor produced during RSV infection, caused a decreased incorporation of glucosamine and SO4 into focal adhesion sites. The decreased incorporation of glucosamine occurred during the G1 period, remained at a plateau during S and increased back to initial levels when DNA synthesis declined; it was inversely related to the size of the fraction of cells that entered the division cycle.