title: Rab13 Traffics on Vesicles Independent of Prenylation.
abstract: Rab GTPases are critical regulators of membrane trafficking. The canonical view is that Rabs are soluble in their inactive GDP-bound form, and only upon activation and conversion to their GTP-bound state are they anchored to membranes through membrane insertion of a C-terminal prenyl group. Here we demonstrate that C-terminal prenylation is not required for Rab13 to associate with and traffic on vesicles. Instead, inactive Rab13 appears to associate with vesicles via protein-protein interactions. Only following activation does Rab13 associate with the plasma membrane, presumably with insertion of the C-terminal prenyl group into the membrane.
authors.affiliation: From the Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada.
authors.forename: Maria S
authors.initials: MS
authors.lastname: Ioannou
authors.affiliation: From the Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada.
authors.forename: Martine
authors.initials: M
authors.lastname: Girard
authors.affiliation: From the Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada peter.mcpherson@mcgill.ca.
authors.forename: Peter S
authors.initials: PS
authors.lastname: McPherson
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D002460:Cell Line; D021961:Cell Membrane Structures / Q000378:metabolism; D022162:Cytoplasmic Vesicles / Q000378:metabolism; D011992:Endosomes / Q000378:metabolism; D020730:Guanine Nucleotide Dissociation Inhibitors / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D008954:Models, Biological; D050505:Mutant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D054730:Protein Interaction Domains and Motifs; D017368:Protein Prenylation; D021381:Protein Transport; D051381:Rats; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D059010:Single-Cell Analysis; D020691:rab GTP-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: C086796:GDP dissociation inhibitor 1; D020730:Guanine Nucleotide Dissociation Inhibitors; D050505:Mutant Proteins; D011994:Recombinant Proteins; C085485:RAB13 protein, human; D020691:rab GTP-Binding Proteins
keywords: DENN domain; DENND2B; GDI; GDP dissociation inhibitor; Rab; TI-VAMP; endosome; guanine nucleotide exchange factor (GEF); protein isoprenylation; vesicles