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Transmembrane Domain Oligomerization Propensity determined by ToxR Assay
Published on: May 26, 2011
It takes two to tango: regulation of G proteins by dimerization
Raphael Gasper1, Simon Meyer, Katja Gotthardt
1Max-Planck-Institut für Molekulare Physiologie, Abteilung Strukturelle Biologie, Dortmund, Germany.
Abstract:
Guanine nucleotide-binding (G) proteins, which cycle between a GDP- and a GTP-bound conformation, are conventionally regulated by GTPase-activating proteins (GAPs) and guanine nucleotide-exchange factors (GEFs), and function by interacting with effector proteins in the GTP-bound 'on' state. Here we present another class of G proteins that are regulated by homodimerization, which we would categorize as G proteins activated by nucleotide-dependent dimerization (GADs). This class includes proteins such as signal recognition particle (SRP), dynamin, septins and the newly discovered Roco protein Leu-rich repeat kinase 2 (LRRK2). We propose that the juxtaposition of the G domains of two monomers across the GTP-binding sites activates the biological function of these proteins and the GTPase reaction.
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