bMERB domains are bivalent Rab8 family effectors evolved by gene duplication
- Max Planck Institute of Molecular Physiology, Germany
- Technische Universität München, Germany
Abstract
In their active GTP-bound form, Rab proteins interact with proteins termed effector molecules. In this study we have thoroughly characterised a Rab effector domain that is present in proteins of the Mical and EHBP families, both known to act in endosomal trafficking. Within our study, we show that these effectors display a preference for Rab8 family proteins (Rab8, 10, 13 and 15) and that some of the effector domains can bind two Rab proteins via separate binding sites. Structural analysis allowed us to explain the specificity towards Rab8 family members and the presence of two similar Rab binding sites that must have evolved via gene duplication. This study is the first to thoroughly characterise a Rab effector protein that contains two separate Rab binding sites within a single domain, allowing Micals and EHBPs to bind two Rabs simultaneously, thus suggesting previously unknown functions of these effector molecules in endosomal trafficking.
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Author details
Funding
Max-Planck-Gesellschaft (No grant number)
- Amrita Rai
- Roger S Goody
- Emerich Mihai Gazdag
- Matthias P Müller
Deutsche Forschungsgemeinschaft (SFB642, project A4)
- Roger S Goody
- Matthias P Müller
Deutsche Forschungsgemeinschaft (SFB1035, project B05)
- Aymelt Itzen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Rai et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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bMERB domains are bivalent Rab8 family effectors evolved by gene duplication
eLife 5:e18675.
https://doi.org/10.7554/eLife.18675
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