An insulin-stimulated ribosomal protein S6 kinase in 3T3-L1 cells.

摘要: Abstract A protein kinase that is stimulated from 2-10-fold by insulin and phosphorylates ribosomal S6 has been characterized in 3T3-L1 cells. The detection of this activity the 100,000 X g supernatant facilitated presence beta-glycerol phosphate or vanadate homogenization buffer. purified 55-fold chromatography on DEAE-cellulose phosphocellulose. resulting specific 584 pmol/min/mg protein. followed gel filtration Ultrogel AcA54 glycerol gradient centrifugation suggests a molecular mass 60,000-70,000 daltons. Mg2+, to lesser extent Mn2+, will support phosphorylation activity. No proteins tested other than are phosphorylated. Based its chromatographic properties substrate specificity, enzyme appears be distinct several kinases known phosphorylate vitro. complete characterization purification may essential elucidation mechanism regulation insulin.