Human glut2 overexpression does not affect glucose-stimulated insulin secretion in min6 cells. Ishihara, Hisamitsu, Tomoichiro Asano, Katsunori Tsukuda, Hideki Katagiri, Kouichi Inukai, Motonobu Anai, Yoshio Yazaki, Jun-Ichi Miyazaki, Masatoshi Kikuchi, and Yoshitomo Oka. Institute for Adult Diseases, Asahi Life Foundation, Nishishinjuku, Shinjuku-ku, Tokyo 160, Japan, Third Department of Internal Medicine and Department of Disease-related Gene Regulation Research (Sandoz), Faculty of Medicine, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113, Japan, Third Department of Internal Medicine, Yamaguchi University School of Medicine, Kogushi, Ube, Yamaguchi 755, Japan
APStracts 2:0142E, 1995.
Accumulated evidence suggests that GLUT2, in addition to its role in glucose transport, may also have other functions in glucose -stimulated insulin secretion. As a first step in addressing this possibility, we have engineered MIN6 cells overexpressing human GLUT2 by transfection with human GLUT2 cDNA. Stable transformants harboring human GLUT2 cDNA exhibited an approximately two-fold increase in 3-O -methylglucose uptake at 0.5 and 15 mM. Glucokinase activity or glucose utilization measured by conversion of [5-3H]glucose to [3H]H2O, was not, however, altered in the MIN6 cells overexpressing human GLUT2. Furthermore, glucose-stimulated insulin secretion was not affected by overexpression of human GLUT2. An abundance of GLUT2, therefore, does not correlate with the glucose-responsiveness of cells in which glycolysis is regulated at the glucose phosphorylating step. These data suggest that GLUT2, by itself, does not have significant functions other than its role in glucose transport in glucose-sensing by MIN6 cells. 

Received 3 April 1995; accepted in final form 19 June 1995.
APS Manuscript Number E157-5.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 11 July 1995.