Premium
Distribution of insulin receptors between plasmalemma and intracellular compartments: Effect of amino acids
Author(s) -
Galbraith Richard A.,
Buse Maria G.
Publication year - 1985
Publication title -
journal of cellular physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.529
H-Index - 174
eISSN - 1097-4652
pISSN - 0021-9541
DOI - 10.1002/jcp.1041220118
Subject(s) - intracellular , serine , amino acid , insulin , receptor , glutamine , biochemistry , isoleucine , insulin receptor , biology , cell , cell surface receptor , chemistry , leucine , endocrinology , phosphorylation , insulin resistance
Insulin receptor regulation was studied in the rat erythroblastic leukemic (EBL) cell in primary culture. After 1–2‐hr incubations in medium containing 12 essential amino acids, glutamine, and serine, EBL cell protein synthesis and insulin receptor concentrations were increased compared to cells incubated without serine. Deficiency of medium isoleucine in the presence of serine rapidly decreased protein synthesis and insulin binding to intact cells. Supplementation of deficient media with serine or isoleucine had no effect on total insulin receptor numbers measured in solubilized cell preparations. Increased insulin binding following serine exposure was seen with binding assays at both 4 and 37°C. Dissociation experiments to quantitate intracellular ligand after 37°C binding assays showed increases in both surface binding and intracellular [ 125 I]insulin accumulation. These data combined with previous observations suggest that amino acids essential for this cell are required for the rapid synthesis of a labile regulatory protein which facilitates the redistribution and/or recycling of insulin receptors.