Phosphorylation of GDI and membrane cycling of rab proteins

FEBS Letters

Steele-Mortimer, Olivia¹  Gruenberg, Jean¹  Clague, Michael J.¹ 

[1] Cell Biology Programme, European Molecular Biology Laboratory, Meyerhofstrasse 1, Heidelberg 69012, Germany

关键词: Small GTP-binding protein;    Rab5;    Rab GDI;    Membrane traffic;    GDI;    guanine nucleotide dissociation inhibitor;    PNS;    post-nuclear supernatant;   

DOI  :  10.1016/0014-5793(93)80244-O

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Membrane transport is known to be regulated by protein phosphorylation and by small GTPases of the rab family. Using specific antibodies, we have identified a 55 kDa phosphorylated protein which co-immunoprecipitated with the cytosolic forms of rab5 and other rab proteins. We demonstrate, on the basis of its mobility in two-dimensional electrophoresis gels and its immunological properties, that this protein is rab GDI (p55/GDI). We also found that, a minor fraction of p55/GDI is membrane associated, but, whilst also complexed with rab proteins, it is not phosphorylated. On the basis of these data we suggest that the cycling of rab proteins between membranes and cytosol is regulated by phosphorylation of p55/GDI.

【 授权许可】

Unknown