GTP analogs suppress uptake but not transport of d‐glucose analogs in Glut1 glucose transporter‐expressing Xenopus oocytes

FEBS Letters

Keller, Konrad¹  Mueckler, Mike M.²  Wellner, Maren¹ 

[1] Institut für Pharmakologie der Freien Universität Berlin, Berlin, Germany;Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA

关键词: Guanine nucleotide;    Glutl glucose transporter;    Xenopus oocyte;   

DOI  :  10.1016/0014-5793(93)81047-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A Xenopus oocyte expression-co-injection system was used to study the influence of guanine nucleotides on D-glucose uptake. GTP analogs like GTPγS and GppNHp had no effect on 3-O-methylglucose transport determined by zero-trans uptake or equilibrium exchange, but suppressed 2-deoxyglucose uptake into Glutl glucose transporter-expressing oocytes by up to 86%. Both GTP analogs showed concentration dependence of their effectiveness, with GTPγS being more potent than GppNHp. No statistically significant differences were observed between groups of oocytes co-injected with water or GDPβS (250 and 500 μM intracellular concentration). Glut1 transporter expression in plasma membrane was not different between water or GTPγS-co-injected oocytes. Thus, inhibition of hexokinase catalytic activity is the most likely causative factor for down-regulation of 2-deoxyglucose uptake.

【 授权许可】

Unknown