Previous Article | Next Article 
Molecular and Cellular Biology, September 2000, p. 6323-6333, Vol. 20, No. 17
0270-7306/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.
Insulin-Activated Protein Kinase C
Bypasses Ras
and Stimulates Mitogen-Activated Protein Kinase Activity and Cell
Proliferation in Muscle Cells
Pietro
Formisano,
Francesco
Oriente,
Francesca
Fiory,
Matilde
Caruso,
Claudia
Miele,
Maria
Alessandra
Maitan,
Francesco
Andreozzi,
Giovanni
Vigliotta,
Gerolama
Condorelli, and
Francesco
Beguinot*
Dipartimento di Biologia e Patologia
Cellulare e Molecolare and Centro di Endocrinologia ed Oncologia
Sperimentale del CNR, Università di Napoli Federico II, Naples
80131, Italy
Received 17 March 2000/Returned for modification 24 April
2000/Accepted 2 June 2000
In L6 muscle cells expressing wild-type human insulin receptors
(L6hIR), insulin induced protein kinase C
(PKC
) and
activities. The expression of kinase-deficient IR mutants abolished
insulin stimulation of these PKC isoforms, indicating that receptor
kinase is necessary for PKC activation by insulin. In L6hIR cells,
inhibition of insulin receptor substrate 1 (IRS-1) expression caused a
90% decrease in insulin-induced PKC
and -
activation and blocked insulin stimulation of mitogen-activated protein kinase (MAPK) and DNA
synthesis. Blocking PKC
with either antisense oligonucleotide or the
specific inhibitor LY379196 decreased the effects of insulin on MAPK
activity and DNA synthesis by >80% but did not affect epidermal
growth factor (EGF)- and serum-stimulated mitogenesis. In contrast,
blocking c-Ras with lovastatin or the use of the L61,S186 dominant
negative Ras mutant inhibited insulin-stimulated MAPK activity and DNA
synthesis by only about 30% but completely blocked the effect of EGF.
PKC
block did not affect Ras activity but almost completely
inhibited insulin-induced Raf kinase activation and coprecipitation
with PKC
. Finally, blocking PKC
expression by antisense
oligonucleotide constitutively increased MAPK activity and DNA
synthesis, with little effect on their insulin sensitivity. We make the
following conclusions. (i) The tyrosine kinase activity of the IR is
necessary for insulin activation of PKC
and -
. (ii) IRS-1
phosphorylation is necessary for insulin activation of these PKCs in
the L6 cells. (iii) In these cells, PKC
plays a unique
Ras-independent role in mediating insulin but not EGF or other growth
factor mitogenic signals.
*
Corresponding author. Mailing address: Dipartimento di
Biologia e Patologia Cellulare e Molecolare, Università di Napoli Federico II, Via S. Pansini, 5, 80131 Naples, Italy. Phone: 39 081 7463248. Fax: 39 081 7463235. E-mail: beguino{at}unina.it.
Molecular and Cellular Biology, September 2000, p. 6323-6333, Vol. 20, No. 17
0270-7306/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.
This article has been cited by other articles:
-
Cassese, A., Esposito, I., Fiory, F., Barbagallo, A. P. M., Paturzo, F., Mirra, P., Ulianich, L., Giacco, F., Iadicicco, C., Lombardi, A., Oriente, F., Van Obberghen, E., Beguinot, F., Formisano, P., Miele, C.
(2008). In Skeletal Muscle Advanced Glycation End Products (AGEs) Inhibit Insulin Action and Induce the Formation of Multimolecular Complexes Including the Receptor for AGEs. J. Biol. Chem.
283: 36088-36099
[Abstract]
[Full Text]
-
Perfetti, A., Oriente, F., Iovino, S., Alberobello, A. T., Barbagallo, A. P. M., Esposito, I., Fiory, F., Teperino, R., Ungaro, P., Miele, C., Formisano, P., Beguinot, F.
(2007). Phorbol Esters Induce Intracellular Accumulation of the Anti-apoptotic Protein PED/PEA-15 by Preventing Ubiquitinylation and Proteasomal Degradation. J. Biol. Chem.
282: 8648-8657
[Abstract]
[Full Text]
-
Corbould, A., Zhao, H., Mirzoeva, S., Aird, F., Dunaif, A.
(2006). Enhanced Mitogenic Signaling in Skeletal Muscle of Women With Polycystic Ovary Syndrome. Diabetes
55: 751-759
[Abstract]
[Full Text]
-
Oriente, F., Andreozzi, F., Romano, C., Perruolo, G., Perfetti, A., Fiory, F., Miele, C., Beguinot, F., Formisano, P.
(2005). Protein Kinase C-{alpha} Regulates Insulin Action and Degradation by Interacting with Insulin Receptor Substrate-1 and 14-3-3{epsilon}. J. Biol. Chem.
280: 40642-40649
[Abstract]
[Full Text]
-
Ginnan, R., Pfleiderer, P. J., Pumiglia, K., Singer, H. A.
(2004). PKC-{delta} and CaMKII-{delta}2 mediate ATP-dependent activation of ERK1/2 in vascular smooth muscle. Am. J. Physiol. Cell Physiol.
286: C1281-C1289
[Abstract]
[Full Text]
-
Fiory, F., Oriente, F., Miele, C., Romano, C., Trencia, A., Alberobello, A. T., Esposito, I., Valentino, R., Beguinot, F., Formisano, P.
(2004). Protein Kinase C-{zeta} and Protein Kinase B Regulate Distinct Steps of Insulin Endocytosis and Intracellular Sorting. J. Biol. Chem.
279: 11137-11145
[Abstract]
[Full Text]
-
Miele, C., Riboulet, A., Maitan, M. A., Oriente, F., Romano, C., Formisano, P., Giudicelli, J., Beguinot, F., Van Obberghen, E.
(2003). Human Glycated Albumin Affects Glucose Metabolism in L6 Skeletal Muscle Cells by Impairing Insulin-induced Insulin Receptor Substrate (IRS) Signaling through a Protein Kinase C{alpha}-mediated Mechanism. J. Biol. Chem.
278: 47376-47387
[Abstract]
[Full Text]
-
Farhang-Fallah, J., Randhawa, V. K., Nimnual, A., Klip, A., Bar-Sagi, D., Rozakis-Adcock, M.
(2002). The Pleckstrin Homology (PH) Domain-Interacting Protein Couples the Insulin Receptor Substrate 1 PH Domain to Insulin Signaling Pathways Leading to Mitogenesis and GLUT4 Translocation. Mol. Cell. Biol.
22: 7325-7336
[Abstract]
[Full Text]
-
Condorelli, G., Trencia, A., Vigliotta, G., Perfetti, A., Goglia, U., Cassese, A., Musti, A. M., Miele, C., Santopietro, S., Formisano, P., Beguinot, F.
(2002). Multiple Members of the Mitogen-activated Protein Kinase Family Are Necessary for PED/PEA-15 Anti-apoptotic Function. J. Biol. Chem.
277: 11013-11018
[Abstract]
[Full Text]
-
Eichhorn, J., Kayali, A. G., Resor, L., Austin, D. A., Rose, D. W., Webster, N. J. G.
(2002). PLC-{gamma}1 Enzyme Activity Is Required for Insulin-Induced DNA Synthesis. Endocrinology
143: 655-664
[Abstract]
[Full Text]
-
Chen, C., Sytkowski, A. J.
(2001). Erythropoietin Activates Two Distinct Signaling Pathways Required for the Initiation and the Elongation of c-myc. J. Biol. Chem.
276: 38518-38526
[Abstract]
[Full Text]
-
Condorelli, G., Vigliotta, G., Trencia, A., Maitan, M. A., Caruso, M., Miele, C., Oriente, F., Santopietro, S., Formisano, P., Beguinot, F.
(2001). Protein Kinase C (PKC)-{alpha} Activation Inhibits PKC-{zeta} and Mediates the Action of PED/PEA-15 on Glucose Transport in the L6 Skeletal Muscle Cells. Diabetes
50: 1244-1252
[Abstract]
[Full Text]
-
Oriente, F., Formisano, P., Miele, C., Fiory, F., Maitan, M. A., Vigliotta, G., Trencia, A., Santopietro, S., Caruso, M., Van Obberghen, E., Beguinot, F.
(2001). Insulin Receptor Substrate-2 Phosphorylation Is Necessary for Protein Kinase Czeta Activation by Insulin in L6hIR Cells. J. Biol. Chem.
276: 37109-37119
[Abstract]
[Full Text]
-
Caruso, M., Maitan, M. A., Bifulco, G., Miele, C., Vigliotta, G., Oriente, F., Formisano, P., Beguinot, F.
(2001). Activation and Mitochondrial Translocation of Protein Kinase Cdelta Are Necessary for Insulin Stimulation of Pyruvate Dehydrogenase Complex Activity in Muscle and Liver Cells. J. Biol. Chem.
276: 45088-45097
[Abstract]
[Full Text]