Myosin VI isoform localized to clathrin-coated vesicles with a role in clathrin-mediated endocytosis.
Myosin VI is involved in membrane traffic and dynamics and is the only myosin known to move towards the minus end of actin filaments. Splice variants of myosin VI with a large insert in the tail domain were specifically expressed in polarized cells containing microvilli. In these polarized cells, endogenous myosin VI containing the large insert was concentrated at the apical domain co-localizing with clathrin- coated pits/vesicles. Using full-length myosin VI and deletion mutants tagged with green fluorescent protein (GFP) we have shown that myosin VI associates and co-localizes with clathrin-coated pits/vesicles by its C-terminal tail. Myosin VI, precipitated from whole cytosol, was present in a protein complex containing adaptor protein (AP)-2 and clathrin, and enriched in purified clathrin-coated vesicles. Over-expression of the tail domain of myosin VI containing the large insert in fibroblasts reduced transferrin uptake in transiently and stably transfected cells by >50%. Myosin VI is the first motor protein to be identified associated with clathrin-coated pits/vesicles and shown to modulate clathrin-mediated endocytosis.
Buss
F
F
Department of Clinical Biochemistry and Wellcome Trust Centre for the Study of Molecular Mechanisms in Disease, Cambridge Institute for Medical Research, University of Cambridge, Addenbrooke's Hospital, Cambridge CB2 2XY, UK. fb1@mole.bio.cam.ac.uk
Arden
S D
SD
Lindsay
M
M
Luzio
J P
JP
Kendrick-Jones
J
J
D000595:Amino Acid Sequence; D000818:Animals; D018938:Caco-2 Cells; D002460:Cell Line; D002645:Chickens; D002966:Clathrin / Q000378:metabolism* / Q000502:physiology; D003034:Coated Pits, Cell-Membrane / Q000378:metabolism*; D004705:Endocytosis / Q000502:physiology*; D049452:Green Fluorescent Proteins; D006801:Humans; D008164:Luminescent Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D018995:Myosin Heavy Chains / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
D002966:Clathrin; D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins; C089785:myosin VI; D049452:Green Fluorescent Proteins; D018995:Myosin Heavy Chains