MISC

2000年4月

Effect of pertussis toxin on insulin-induced signal transduction in rat adipocytes and soleus muscles

CELLULAR SIGNALLING
  • Y Kanoh
  • ,
  • T Ishizuka
  • ,
  • H Morita
  • ,
  • M Ishizawa
  • ,
  • A Miura
  • ,
  • K Kajita
  • ,
  • M Kimura
  • ,
  • T Suzuki
  • ,
  • H Sakuma
  • ,
  • K Yasuda

12
4
開始ページ
223
終了ページ
232
記述言語
英語
掲載種別
DOI
10.1016/S0898-6568(99)00081-9
出版者・発行元
ELSEVIER SCIENCE INC

It has been reported that pertussis toxin (PTX) suppresses the function of trimeric guanine nucleotide binding protein (G-protein). We examined the effect of PTX on insulin-induced glucose uptake, diacylglycerol (DG)-protein kinase C (PKC) signalling, phosphatidylinositol (PI) 3-kinase and PKC zeta activation and insulin-induced tyrosine phosphorylation of Gi alpha to clarify the role of G-protein for insulin-mediated signal transduction mechanism in rat adipocytes and soleus muscles. Isolated adipocytes and soleus muscles were preincubated with 0.01 similar to 1 ng/ml PTX for 2 hours, followed by stimulation with 10-100 nM insulin or 1 mu M tetradecanoyl phorbol-13-acetate (TPA). Pretreatment with PTX resulted in dose-responsive decreases in insulin-stimulated [H-3]2-deoxyglucose (DOG) uptake, and unchanged TPA-stimulated [H-3]2-DOG uptake, without affecting basal [3H]2-DOG uptake. In adipocytes, insulin-induced DG-PKC signalling, PI 3-kinase activation and PKC zeta translocation from cytosol to the membrane were suppressed when treated with PTX, despite no changes in [I-125]insulin-specific binding and insulin receptor tyrosine kinase activity. Moreover, to elucidate insulin-stimulated tyrosine phosphorylation of 40 kDa alpha-subunit of G-protein (Gi alpha-2), adipocytes were stimulated with 10 nM insulin for 10 minutes, homogenized, immunoprecipitated with anti-phosphotyrosine antibody, and immunoblotted with anti-Gi alpha-2 antibody. Insulin-induced tyrosine phosphorylation of Gi alpha-2 was found by immunoblot analysis with anti-Gi alpha-2 antibody. These results suggest that G-protein regulates DG-PKC signalling by binding of Gi alpha-2 with GTP and PI 3-kinase-PKC zeta signalling by releasing of G beta gamma via dissociation of trimeric G-protein after insulin receptor tyrosine phosphorylation in insulin-sensitive tissues. (C) 2000 Elsevier Science Inc. All rights reserved.

Web of Science ® 被引用回数 : 15

リンク情報
DOI
https://doi.org/10.1016/S0898-6568(99)00081-9
CiNii Articles
http://ci.nii.ac.jp/naid/80011655563
PubMed
https://www.ncbi.nlm.nih.gov/pubmed/10781929
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000086754600004&DestApp=WOS_CPL