CaMKII-Mediated Phosphorylation of the Myosin Motor Myo1c Is Required for Insulin-Stimulated GLUT4 Translocation in Adipocytes

Ming Fai Yip, Georg Ramm, Mark Larance, Kyle L. Hoehn, Mark Wagner, Michael Guilhaus, David E. James

Research output: Contribution to journalArticle

76 Citations (Scopus)

Abstract

The unconventional myosin Myo1c has been implicated in insulin-regulated GLUT4 translocation to the plasma membrane in adipocytes. We show that Myo1c undergoes insulin-dependent phosphorylation at S701. Phosphorylation was accompanied by enhanced 14-3-3 binding and reduced calmodulin binding. Recombinant CaMKII phosphorylated Myo1c in vitro and siRNA knockdown of CaMKIIδ abolished insulin-dependent Myo1c phosphorylation in vivo. CaMKII activity was increased upon insulin treatment and the CaMKII inhibitors CN21 and KN-62 or the Ca2+ chelator BAPTA-AM blocked insulin-dependent Myo1c phosphorylation and insulin-stimulated glucose transport in adipocytes. Myo1c ATPase activity was increased after CaMKII phosphorylation in vitro and after insulin stimulation of CHO/IR/IRS-1 cells. Expression of wild-type Myo1c, but not S701A or ATPase dead mutant K111A, rescued the inhibition of GLUT4 translocation by siRNA-mediated Myo1c knockdown. These data suggest that insulin regulates Myo1c function via CaMKII-dependent phosphorylation, and these events play a role in insulin-regulated GLUT4 trafficking in adipocytes likely involving Myo1c motor activity.

Original languageEnglish
Pages (from-to)384-398
Number of pages15
JournalCell Metabolism
Volume8
Issue number5
DOIs
StatePublished - Nov 5 2008

Fingerprint

Calcium-Calmodulin-Dependent Protein Kinase Type 2
Myosins
Adipocytes
Phosphorylation
Insulin
KN 62
Small Interfering RNA
Adenosine Triphosphatases
Calmodulin
Chelating Agents
Motor Activity
Cell Membrane
Glucose

Keywords

  • HUMDISEASE
  • SIGNALING
  • SYSBIO

ASJC Scopus subject areas

  • Cell Biology
  • Molecular Biology
  • Physiology

Cite this

CaMKII-Mediated Phosphorylation of the Myosin Motor Myo1c Is Required for Insulin-Stimulated GLUT4 Translocation in Adipocytes. / Yip, Ming Fai; Ramm, Georg; Larance, Mark; Hoehn, Kyle L.; Wagner, Mark; Guilhaus, Michael; James, David E.

In: Cell Metabolism, Vol. 8, No. 5, 05.11.2008, p. 384-398.

Research output: Contribution to journalArticle

Yip, Ming Fai ; Ramm, Georg ; Larance, Mark ; Hoehn, Kyle L. ; Wagner, Mark ; Guilhaus, Michael ; James, David E. / CaMKII-Mediated Phosphorylation of the Myosin Motor Myo1c Is Required for Insulin-Stimulated GLUT4 Translocation in Adipocytes. In: Cell Metabolism. 2008 ; Vol. 8, No. 5. pp. 384-398.
@article{9a07e6b614914fbfb2b5d2f6f0ac718e,
title = "CaMKII-Mediated Phosphorylation of the Myosin Motor Myo1c Is Required for Insulin-Stimulated GLUT4 Translocation in Adipocytes",
abstract = "The unconventional myosin Myo1c has been implicated in insulin-regulated GLUT4 translocation to the plasma membrane in adipocytes. We show that Myo1c undergoes insulin-dependent phosphorylation at S701. Phosphorylation was accompanied by enhanced 14-3-3 binding and reduced calmodulin binding. Recombinant CaMKII phosphorylated Myo1c in vitro and siRNA knockdown of CaMKIIδ abolished insulin-dependent Myo1c phosphorylation in vivo. CaMKII activity was increased upon insulin treatment and the CaMKII inhibitors CN21 and KN-62 or the Ca2+ chelator BAPTA-AM blocked insulin-dependent Myo1c phosphorylation and insulin-stimulated glucose transport in adipocytes. Myo1c ATPase activity was increased after CaMKII phosphorylation in vitro and after insulin stimulation of CHO/IR/IRS-1 cells. Expression of wild-type Myo1c, but not S701A or ATPase dead mutant K111A, rescued the inhibition of GLUT4 translocation by siRNA-mediated Myo1c knockdown. These data suggest that insulin regulates Myo1c function via CaMKII-dependent phosphorylation, and these events play a role in insulin-regulated GLUT4 trafficking in adipocytes likely involving Myo1c motor activity.",
keywords = "HUMDISEASE, SIGNALING, SYSBIO",
author = "Yip, {Ming Fai} and Georg Ramm and Mark Larance and Hoehn, {Kyle L.} and Mark Wagner and Michael Guilhaus and James, {David E.}",
year = "2008",
month = "11",
day = "5",
doi = "10.1016/j.cmet.2008.09.011",
language = "English",
volume = "8",
pages = "384--398",
journal = "Cell Metabolism",
issn = "1550-4131",
publisher = "Cell Press",
number = "5",

}

TY - JOUR

T1 - CaMKII-Mediated Phosphorylation of the Myosin Motor Myo1c Is Required for Insulin-Stimulated GLUT4 Translocation in Adipocytes

AU - Yip, Ming Fai

AU - Ramm, Georg

AU - Larance, Mark

AU - Hoehn, Kyle L.

AU - Wagner, Mark

AU - Guilhaus, Michael

AU - James, David E.

PY - 2008/11/5

Y1 - 2008/11/5

N2 - The unconventional myosin Myo1c has been implicated in insulin-regulated GLUT4 translocation to the plasma membrane in adipocytes. We show that Myo1c undergoes insulin-dependent phosphorylation at S701. Phosphorylation was accompanied by enhanced 14-3-3 binding and reduced calmodulin binding. Recombinant CaMKII phosphorylated Myo1c in vitro and siRNA knockdown of CaMKIIδ abolished insulin-dependent Myo1c phosphorylation in vivo. CaMKII activity was increased upon insulin treatment and the CaMKII inhibitors CN21 and KN-62 or the Ca2+ chelator BAPTA-AM blocked insulin-dependent Myo1c phosphorylation and insulin-stimulated glucose transport in adipocytes. Myo1c ATPase activity was increased after CaMKII phosphorylation in vitro and after insulin stimulation of CHO/IR/IRS-1 cells. Expression of wild-type Myo1c, but not S701A or ATPase dead mutant K111A, rescued the inhibition of GLUT4 translocation by siRNA-mediated Myo1c knockdown. These data suggest that insulin regulates Myo1c function via CaMKII-dependent phosphorylation, and these events play a role in insulin-regulated GLUT4 trafficking in adipocytes likely involving Myo1c motor activity.

AB - The unconventional myosin Myo1c has been implicated in insulin-regulated GLUT4 translocation to the plasma membrane in adipocytes. We show that Myo1c undergoes insulin-dependent phosphorylation at S701. Phosphorylation was accompanied by enhanced 14-3-3 binding and reduced calmodulin binding. Recombinant CaMKII phosphorylated Myo1c in vitro and siRNA knockdown of CaMKIIδ abolished insulin-dependent Myo1c phosphorylation in vivo. CaMKII activity was increased upon insulin treatment and the CaMKII inhibitors CN21 and KN-62 or the Ca2+ chelator BAPTA-AM blocked insulin-dependent Myo1c phosphorylation and insulin-stimulated glucose transport in adipocytes. Myo1c ATPase activity was increased after CaMKII phosphorylation in vitro and after insulin stimulation of CHO/IR/IRS-1 cells. Expression of wild-type Myo1c, but not S701A or ATPase dead mutant K111A, rescued the inhibition of GLUT4 translocation by siRNA-mediated Myo1c knockdown. These data suggest that insulin regulates Myo1c function via CaMKII-dependent phosphorylation, and these events play a role in insulin-regulated GLUT4 trafficking in adipocytes likely involving Myo1c motor activity.

KW - HUMDISEASE

KW - SIGNALING

KW - SYSBIO

UR - http://www.scopus.com/inward/record.url?scp=54849439728&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=54849439728&partnerID=8YFLogxK

U2 - 10.1016/j.cmet.2008.09.011

DO - 10.1016/j.cmet.2008.09.011

M3 - Article

C2 - 19046570

AN - SCOPUS:54849439728

VL - 8

SP - 384

EP - 398

JO - Cell Metabolism

JF - Cell Metabolism

SN - 1550-4131

IS - 5

ER -