Two‐dimensional distribution of Gi2α in the plasma membrane: a critical evaluation by immunocytochemistry

FEBS Letters

Inuo, Chisato¹  Takahashi, Yukiko¹  Fujimoto, Toyoshi¹  Nomura, Ryuji¹  Asano, Tomiko² 

[1]Department of Anatomy and Cell Biology, Gunma University School of Medicine, 3-39-22 Showa-machi, Maebashi 371, Japan

[2]Department of Biochemistry, Institute for Developmental Research, Aichi Human Service Center, 713-8 Kamiya-cho, Kasugai, Aichi 480-03, Japan

关键词: Caveola;    Plasma membrane;    Gi2α;    Immunocytochemistry;    BSA;    bovine serum albumin;    TIFF;    Triton X-100-insoluble floating fraction;   

DOI  :  10.1016/S0014-5793(97)01114-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Caveolae have been postulated as a center for signal transduction, because many signaling molecules are concentrated in caveolin-rich fractions. We took G_i2α as an example and examined whether it is constitutively concentrated in caveolae. First, the behavior of caveolin and G_i2α in density-equilibrium ultracentrifugation was reexamined. By collecting fractions efficiently, caveolin and G_i2α were found to distribute differently. Secondly, by novel immunocytochemical methods it was found that the labeling density of G_i2α was 2.29 times higher in caveolae than in the non-caveolar plasma membrane. The results indicate that the concentration of G_i2α in caveolae is lower than deduced from most biochemical studies.

【 授权许可】

Unknown