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Rab Proteins

Rab Proteins

Rab proteins constitute the largest family of monomeric GTPases, of which 70 members are present in humans. Rab proteins and their effectors regulate consecutive stages of vesicle transport such as vesicle transport, docking, and fusion to the correct recipient membrane.
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Coat Assembly and GTPases

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Related Experiment Video

Updated: Jul 5, 2026

Monitoring Activation of the Antiviral Pattern Recognition Receptors RIG-I And PKR By Limited Protease Digestion and Native PAGE

Monitoring Activation of the Antiviral Pattern Recognition Receptors RIG-I And PKR By Limited Protease Digestion and Native PAGE

Published on: July 29, 2014

Varp interacts with Rab38 and functions as its potential effector.

Fang Wang¹, Haiwei Zhang, Xinjun Zhang

¹Key Laboratory of Beijing, College of Life Science, Beijing Normal University, Beijing 100875, China.

Biochemical and Biophysical Research Communications

|May 15, 2008

Summary

This summary is machine-generated.

Varp protein interacts with Rab38, acting as a potential effector. This protein also functions as a guanine nucleotide exchange factor (GEF) for different Rab proteins in cells.

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Last Updated: Jul 5, 2026

Monitoring Activation of the Antiviral Pattern Recognition Receptors RIG-I And PKR By Limited Protease Digestion and Native PAGE

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Rab10 Phosphorylation Detection by LRRK2 Activity Using SDS-PAGE with a Phosphate-binding Tag

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Published on: December 14, 2017

Area of Science:

Molecular biology
Cell biology
Protein interactions

Background:

Varp (VPS9 domain and ankyrin repeats) is a novel protein.
Varp regulates endosome dynamics and acts as a guanine nucleotide exchange factor (GEF) for Rab21.
Previous research established Varp's role in endosomal trafficking.

Purpose of the Study:

To investigate the function of Varp further.
To identify novel Varp-interacting proteins.
To elucidate the interaction between Varp and Rab38.

Main Methods:

Yeast two-hybrid screening to identify Varp-associated proteins.
In vitro and in vivo binding assays to confirm Varp-Rab38 interaction.
Analysis of Varp recruitment to Rab38-positive organelles.

Main Results:

Rab38 was identified as a Varp-interacting protein.
Varp physically interacts with Rab38, preferentially binding the GTP-bound form.
Varp is recruited to Rab38-positive organelles dependent on its ankyrin repeat 1 (ANK1).

Conclusions:

Varp is a potential effector protein for Rab38.
Varp functions as both an effector and a GEF by interacting with distinct Rab proteins.
This dual role highlights Varp's versatility in regulating cellular processes.