Insulin receptor synthesis and turnover in differentiating 3T3-L1 preadipocytes.

Publisher Website
Google Scholar
Abstract
A density-shift method is described for analyzing insulin receptor synthesis and turnover in cultured cells labeled with heavy amino acids (2H, 13C and 15N). Solubilized newly synthesized heavy and old light receptors were separated by isopycnic banding on CsCl gradients and then quantitated. Insulin receptor synthesis and turnover were studied by this technique in 3T3-Li preadipocytes which undergo an increase in insulin binding capacity during differentiation. The increase in insulin binding capacity is evidently a consequence of new receptor synthesis; the insulin receptor has a relatively short half-life (6.7 h), and an increased rate of receptor synthesis contributes to the increase of insulin receptor level during differentiation.