Control by insulin and insulin-related growth factor 1 of protein synthesis in a cell-free translational system from chick-embryo fibroblasts.
Insulin and insulin-related growth factor 1 (IGF-1) increase by 1.5-1.6-fold the rate of [3H]leucine incorporation into protein in primary monolayer cultures of chick-embryo fibroblasts (CEF); half-maximal hormone concentrations are 10 and 0.25 nM respectively. To investigate the mechanism of this effect, a rapid method is used to prepare a lysate from CEF which is active in protein synthesis. Lysate derived from cells treated for 30-150 min with insulin synthesized protein at 1.8-3.0-fold greater rate than did controls; the increased rate persisted for 20 min in vitro. Pactamycin (0.5 microM), an inhibitor of peptide-chain initiation, inhibited protein synthesis by 50% in lysates derived from insulin-treated and control cells. Thus insulin and IGF-1 cause an increase in the protein-synthesis rate in vivo, which persists in cell-free protein-synthesizing lysates of CEF.
Pierce
M W
MW
Howard Hughes Medical Institute Laboratories, Harvard Medical School, Massachusetts General Hospital, Boston 02114.
Coombs
K
K
Young
M
M
Avruch
J
J
D000818:Animals; D002474:Cell-Free System / Q000187:drug effects; D002478:Cells, Cultured; D002642:Chick Embryo; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D007328:Insulin / Q000494:pharmacology*; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D007930:Leucine / Q000378:metabolism; D010142:Pactamycin / Q000494:pharmacology; D014176:Protein Biosynthesis; D011506:Proteins / Q000235:genetics; D011691:Puromycin / Q000494:pharmacology; D013002:Somatomedins / Q000494:pharmacology*
D007328:Insulin; D011506:Proteins; D013002:Somatomedins; D010142:Pactamycin; D011691:Puromycin; D007334:Insulin-Like Growth Factor I; D007930:Leucine