The neuron-specific kinesin superfamily protein KIF1A is a unique monomeric motor for anterograde axonal transport of synaptic vesicle precursors.
Axonal transport has been intensively examined as a good model for studying the mechanism of organelle transport in cells, but it is still unclear how different types of membrane organelles are transported through the nerve axon. To elucidate the function of this mechanism, we have cloned KIF1A, a novel neuron-specific kinesin superfamily motor that was discovered to be a monomeric, globular molecule and that had the fastest reported anterograde motor activity (1.2 microns/s). To identify its cargo, membranous organelles were isolated from the axon. KIF1A was associated with organelles that contained synaptic vesicle proteins such as synaptotagmin, synaptophysin, and Rab3A. However, this organelle did not contain SV2, another synaptic vesicle protein, nor did it contain presynaptic membrane proteins, such as syntaxin 1A or SNAP-25, or other known anterograde motor proteins, such as kinesin and KIF3. Thus, we suggest that the membrane proteins are sorted into different classes of transport organelles in the cell body and are transported by their specific motor proteins through the axon.
Okada
Y
Y
Department of Anatomy and Cell Biology, Faculty of Medicine, University of Tokyo, Japan.
Yamazaki
H
H
Sekine-Aizawa
Y
Y
Hirokawa
N
N
D000595:Amino Acid Sequence; D000818:Animals; D000954:Antigens, Surface / Q000032:analysis / Q000235:genetics / Q000378:metabolism* / Q000502:physiology* / Q000648:ultrastructure; D001370:Axonal Transport / Q000235:genetics / Q000502:physiology*; D001483:Base Sequence; D001692:Biological Transport; D002135:Calcium-Binding Proteins; D002420:Cauda Equina / Q000166:cytology / Q000502:physiology; D002458:Cell Fractionation; D016764:Cell Polarity / Q000235:genetics / Q000502:physiology*; D003001:Cloning, Molecular; D019204:GTP-Binding Proteins / Q000378:metabolism; D015151:Immunoblotting; D007425:Intracellular Membranes / Q000502:physiology; D016547:Kinesins / Q000235:genetics / Q000378:metabolism / Q000502:physiology* / Q000648:ultrastructure; D008562:Membrane Glycoproteins / Q000032:analysis / Q000378:metabolism; D008565:Membrane Proteins / Q000032:analysis / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D009038:Motion; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism* / Q000502:physiology* / Q000648:ultrastructure; D015388:Organelles / Q000502:physiology; D011994:Recombinant Proteins / Q000378:metabolism / Q000648:ultrastructure; D017386:Sequence Homology, Amino Acid; D013572:Synaptic Vesicles / Q000502:physiology*; D016708:Synaptophysin / Q000378:metabolism; D050825:Synaptosomal-Associated Protein 25; D050857:Synaptotagmins; D050827:Syntaxin 1; D020692:rab3 GTP-Binding Proteins
D000954:Antigens, Surface; D002135:Calcium-Binding Proteins; C490576:Kif1a protein, mouse; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D011994:Recombinant Proteins; C494209:Snap25 protein, mouse; C494214:Stx1a protein, mouse; C489614:Sv2a protein, mouse; D016708:Synaptophysin; D050825:Synaptosomal-Associated Protein 25; D050827:Syntaxin 1; D050857:Synaptotagmins; D019204:GTP-Binding Proteins; D016547:Kinesins; D020692:rab3 GTP-Binding Proteins