| First Author | Barthel A | Year | 1998 |
| Journal | Biochem Biophys Res Commun | Volume | 243 |
| Issue | 2 | Pages | 509-13 |
| PubMed ID | 9480839 | Mgi Jnum | J:45996 |
| Mgi Id | MGI:1196799 | Doi | 10.1006/bbrc.1998.8134 |
| Citation | Barthel A, et al. (1998) Protein kinase C modulates the insulin-stimulated increase in Akt1 and Akt3 activity in 3T3-L1 adipocytes. Biochem Biophys Res Commun 243(2):509-13 |
| abstractText | In the present studies, we have compared the properties of two members of the Akt family of ser/thr kinases, Akt1 and Akt3. First, we demonstrate that both 3T3-L1 fibroblasts and adipocytes express Akt3 mRNA by RT-PCR and sequencing of the resultant PCR product. Second, we show that insulin stimulates the enzymatic activity of Akt1 and Akt3 15-and 7-fold, respectively. We then investigated the ability of protein kinase C to regulate Akt1 and 3. Neither enzyme was activated by stimulation of protein kinase C, however, the insulin-stimulated increases in activity of both isozymes were found to be comparably inhibited by prior protein kinase C activation. Since this inhibition could have resulted from an interaction of the pleckstrin homology domain of the Akt with protein kinase C, we also examined the ability of a mutant Akt1 lacking this domain to be regulated by this enzyme. The insulin-stimulated increase in enzymatic activity of this mutant Akt was regulated by PKC activation like the wild type enzyme. These results indicate that Akt1 and 3 are similarly stimulated by insulin and this stimulation is inhibited by prior activation of protein kinase C through a mechanism that is independent of the presence of the pleckstrin homology domain. |
