title: Identification and characterization of multiple novel Rab-myosin Va interactions.
abstract: Myosin Va is a widely expressed actin-based motor protein that binds members of the Rab GTPase family (3A, 8A, 10, 11A, 27A) and is implicated in many intracellular trafficking processes. To our knowledge, myosin Va has not been tested in a systematic screen for interactions with the entire Rab GTPase family. To that end, we report a yeast two-hybrid screen of all human Rabs for myosin Va-binding ability and reveal 10 novel interactions (3B, 3C, 3D, 6A, 6A', 6B, 11B, 14, 25, 39B), which include interactions with three new Rab subfamilies (Rab6, Rab14, Rab39B). Of interest, myosin Va interacts with only a subset of the Rabs associated with the endocytic recycling and post-Golgi secretory systems. We demonstrate that myosin Va has three distinct Rab-binding domains on disparate regions of the motor (central stalk, an alternatively spliced exon, and the globular tail). Although the total pool of myosin Va is shared by several Rabs, Rab10 and Rab11 appear to be the major determinants of its recruitment to intracellular membranes. We also present evidence that myosin Va is necessary for maintaining a peripheral distribution of Rab11- and Rab14-positive endosomes.
authors.affiliation: Molecular Cell Biology Laboratory, School of Biochemistry and Cell Biology, Biosciences Institute, University College Cork, Cork, Ireland Centre de Recherche, Molecular Mechanisms of Intracellular Transport, Institut Curie, CNRS UMR144, F-75248 Paris, France School of Biochemistry and Immunology, Trinity College, Dublin 2, Ireland Structure and Membrane Compartments, Institut Curie, CNRS UMR144, F-75248 Paris, France Cell and Tissue Imaging Facility (PICT-IBiSA), Institut Curie, CNRS UMR144, F-75248 Paris, France.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Lindsay
authors.forename: Florence
authors.initials: F
authors.lastname: Jollivet
authors.forename: Conor P
authors.initials: CP
authors.lastname: Horgan
authors.forename: Amir R
authors.initials: AR
authors.lastname: Khan
authors.forename: Graça
authors.initials: G
authors.lastname: Raposo
authors.forename: Mary W
authors.initials: MW
authors.lastname: McCaffrey
authors.forename: Bruno
authors.initials: B
authors.lastname: Goud
mesh_terms: D001665:Binding Sites / Q000235:genetics; D015153:Blotting, Western; D045744:Cell Line, Tumor; D011992:Endosomes / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D009154:Mutation; D018995:Myosin Heavy Chains / Q000235:genetics / Q000378:metabolism*; D024701:Myosin Type V / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D034622:RNA Interference; D059008:Time-Lapse Imaging / Q000379:methods; D020798:Two-Hybrid System Techniques; D020691:rab GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C094135:Rab6 protein; D049452:Green Fluorescent Proteins; C077511:MYO5A protein, human; D024701:Myosin Type V; C553411:Rab14 protein, human; C547812:Rab39B protein, human; D018995:Myosin Heavy Chains; D020691:rab GTP-Binding Proteins