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Updated: Apr 15, 2026

Rab10 Phosphorylation Detection by LRRK2 Activity Using SDS-PAGE with a Phosphate-binding Tag
Published on: December 14, 2017
Kinetic activation of Rab8 guanine nucleotide exchange factor Rabin8 by Rab11
Shanshan Feng1, Bin Wu, Johan Peränen
1Department of Biology, University of Pennsylvania, Philadelphia, PA, 19104, USA, pennshan@gmail.com.
Abstract:
The Rab family of small GTPases acts as molecular switches that control various stages of vesicular transport. Rab8 functions in exocytic trafficking from the trans-Golgi network (TGN) and recycling endosomes to the plasma membrane. Rabin8 is a major guanine nucleotide exchange factor (GEF) for Rab8. It activates Rab8 by catalyzing its GDP release for subsequent GTP loading. However, how Rabin8 itself is activated in cells is unclear. Recently, it was found that Rabin8 is a downstream effector of Rab11, which controls vesicle exit from the recycling endosomes. Rab11, in its GTP-bound form, stimulates the GEF activity of Rabin8. The Rab11-Rabin8-Rab8 interactions thus couple vesicle generation from the donor compartment to its delivery to plasma membrane. Here we describe the methods we used to express and purify several Rab proteins, and to assay for the effect of Rab11 in the kinetic activation of Rabin8 GEF activity.
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