作者: Harry Rubin
DOI: 10.1016/S0065-230X(05)93001-7
关键词: DNA synthesis 、 Cell surface receptor 、 Cytosol 、 Cell growth 、 Glucose transporter 、 Neoplastic transformation 、 Cell biology 、 Biology 、 PI3K/AKT/mTOR pathway 、 Phosphorylation
摘要: Growth factors are polypeptides that combine with specific membrane receptors on animal cells to stimulate proliferation, but they also glucose transport, uridine phosphorylation, intermediary metabolism, protein synthesis, and other processes of the coordinate response. There a variety nonspecific surface action treatments which same set reactions as growth do, synthesis is most directly related onset DNA synthesis. Mg(2+) required for very wide range cellular reactions, including all phosphoryl transfers, its deprivation inhibits components response have so far been tested. raise level free closer optimum initiation The resulting increase in accelerates progression through G1 mitosis. None 3 major cations similarly involved regulation, although internal pH may play an auxiliary role. Almost 10(5) externally bound divalent displaced from membranes every attached insulin molecule, implying conformational change releases enough plasma account cytosolic Mg(2+). It proposed mTOR, central control point PI 3-K kinase cascade stimulated by insulin, regulated MgATP(2-) varies Other elements such increased transport phosphorylation dependent upon Deprivation neoplastically transformed cultures normalizes their appearance behavior raises abnormally low Ca(2+) concentration. Tight packing at high saturation density confers normalizing effects, retained few days after subculture density. results suggest activity within cell regulator normal growth, loss membrane-mediated can neoplastic phenotype.