The guanine nucleotide exchange factor FLJ00068 activates Rac1 in adipocyte insulin signaling

FEBS Lett. 2020 Dec;594(24):4370-4380. doi: 10.1002/1873-3468.13939. Epub 2020 Oct 9.

Abstract

Insulin stimulates glucose uptake via the translocation of the glucose transporter GLUT4 to the plasma membrane in adipocytes. Several lines of evidence suggest that the small GTPase Rac1 plays an important role in insulin-stimulated glucose uptake in skeletal muscle and adipocytes. The purpose of this study is to investigate the mechanisms whereby Rac1 is regulated in adipocyte insulin signaling. Here, we show that knockdown of the guanine nucleotide exchange factor FLJ00068 inhibits Rac1 activation and GLUT4 translocation by insulin and a constitutively activated form of the protein kinase Akt2. Furthermore, constitutively activated FLJ00068 induced Rac1 activation and Rac1-dependent GLUT4 translocation. Collectively, these results suggest the involvement of FLJ00068 downstream of Akt2 in insulin-stimulated glucose uptake signaling in adipocytes.

Keywords: Akt2; GLUT4; Rac1; adipocyte; guanine nucleotide exchange factor; insulin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3-L1 Cells
  • Adipocytes / enzymology
  • Adipocytes / metabolism*
  • Animals
  • Enzyme Activation
  • Glucose / metabolism
  • Glucose Transporter Type 4 / metabolism
  • Guanine Nucleotide Exchange Factors / metabolism*
  • Insulin / metabolism*
  • Mice
  • Neuropeptides / metabolism*
  • Proto-Oncogene Proteins c-akt / metabolism
  • Signal Transduction*
  • rac1 GTP-Binding Protein / metabolism*

Substances

  • Glucose Transporter Type 4
  • Guanine Nucleotide Exchange Factors
  • Insulin
  • Neuropeptides
  • PLEKHG4 protein, mouse
  • Rac1 protein, mouse
  • Slc2a4 protein, mouse
  • Akt2 protein, mouse
  • Proto-Oncogene Proteins c-akt
  • rac1 GTP-Binding Protein
  • Glucose