Rubin Darrell, Ismail-Beigi Faramarz
Department of Pathology, Case Western Reserve University, Cleveland, OH, USA.
Arch Biochem Biophys. 2004 Nov 15;431(2):224-32. doi: 10.1016/j.abb.2004.08.007.
Approximately 50% of Glut1 in the plasma membrane of Clone 9 cells is localized to the detergent-resistant membrane (DRM) fraction. Acute exposure (90 min) to 5mM azide stimulated glucose transport by approximately 4.7-fold and increased the abundance of Glut1 in the non-DRM fraction of the plasma membrane by approximately 2.9-fold while the abundance of Glut1 in the DRMs was not changed. In parallel experiments, approximately 17 h exposure to azide further increased the rate of glucose transport over that observed at 90 min by approximately 33% and increased plasma membrane Glut1 content by approximately 3.5-fold over control. The increase in total plasma membrane Glut1 reflected a approximately 4.7-fold increase of Glut1 content in the non-DRM fraction and a approximately 2.6-fold increase in the DRMs. We conclude that acute exposure to azide increases Glut1 content in the non-DRM fractions, while prolonged exposure to azide increases the Glut1 content in both non-DRM and DRM fractions. These changes may play an important role in the stimulation of glucose transport in response to the inhibition of oxidative phosphorylation.
克隆9细胞质膜中约50%的葡萄糖转运蛋白1(Glut1)定位于抗去污剂膜(DRM)组分。急性暴露(90分钟)于5 mM叠氮化物可使葡萄糖转运增加约4.7倍,并使质膜非DRM组分中Glut1的丰度增加约2.9倍,而DRM中Glut1的丰度未改变。在平行实验中,与90分钟时相比,约17小时暴露于叠氮化物使葡萄糖转运速率进一步增加约33%,质膜Glut1含量比对照增加约3.5倍。质膜总Glut1的增加反映了非DRM组分中Glut1含量增加约4.7倍,DRM中增加约2.6倍。我们得出结论,急性暴露于叠氮化物会增加非DRM组分中的Glut1含量,而长时间暴露于叠氮化物会增加非DRM和DRM组分中的Glut1含量。这些变化可能在响应氧化磷酸化抑制而刺激葡萄糖转运中起重要作用。