Myosin V attachment to cargo requires the tight association of two functional subdomains.
The myosin V carboxyl-terminal globular tail domain is essential for the attachment of myosin V to all known cargoes. Previously, the globular tail was viewed as a single, functional entity. Here, we show that the globular tail of the yeast myosin Va homologue, Myo2p, contains two structural subdomains that have distinct functions, namely, vacuole-specific and secretory vesicle-specific movement. Biochemical and genetic analyses demonstrate that subdomain I tightly associates with subdomain II, and that the interaction does not require additional proteins. Importantly, although neither subdomain alone is functional, simultaneous expression of the separate subdomains produces a functional complex in vivo. Our results suggest a model whereby intramolecular interactions between the globular tail subdomains help to coordinate the transport of multiple distinct cargoes by myosin V.
Pashkova
Natasha
N
Department of Biochemistry, University of Iowa, Iowa City, IA 52242, USA.
Catlett
Natalie L
NL
Novak
Jennifer L
JL
Wu
Guanming
G
Lu
Renne
R
Cohen
Robert E
RE
Weisman
Lois S
LS
D000595:Amino Acid Sequence; D001665:Binding Sites; D001692:Biological Transport / Q000502:physiology; D022162:Cytoplasmic Vesicles / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008954:Models, Biological; D008969:Molecular Sequence Data; D009154:Mutation; D018995:Myosin Heavy Chains / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D024701:Myosin Type V / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D009687:Nuclear Proteins / Q000378:metabolism; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D011956:Receptors, Cell Surface / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D022142:Secretory Vesicles / Q000378:metabolism; D014162:Transfection; D014357:Trypsin / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D014617:Vacuoles / Q000378:metabolism; D033921:Vesicular Transport Proteins / Q000378:metabolism
C110443:KAR9 protein, S cerevisiae; C077512:MYO2 protein, S cerevisiae; D008869:Microtubule-Associated Proteins; D009687:Nuclear Proteins; D010446:Peptide Fragments; D011956:Receptors, Cell Surface; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; C472499:VAC17 protein, S cerevisiae; D033921:Vesicular Transport Proteins; C087665:kinesin-like protein 1; D014357:Trypsin; D024701:Myosin Type V; D018995:Myosin Heavy Chains