Fast transport of neurofilament protein along microtubules in squid axoplasm.
Using squid axoplasm as a model system, we have visualized the fast transport of non-filamentous neurofilament protein particles along axonal microtubules. This transport occurs at speeds of 0.5-1.0 microm/second and the majority of neurofilament particles stain with kinesin antibody. These observations demonstrate, for the first time, that fast (0.5-1.0 microm/second) transport of neurofilament proteins occurs along microtubules. In addition, our studies suggest that neurofilament protein can be transported as non-membrane bound, nonfilamentous subunits along axons, and that the transport is kinesin-dependent. Microtubule-based fast transport might therefore provide a mechanism for the distribution and turnover of neurofilament, and perhaps other cytoskeletal proteins, throughout neurons.
Prahlad
V
V
Northwestern University Medical School, Department of Cell and Molecular Biology, Chicago, IL 60611, USA.
Helfand
B T
BT
Langford
G M
GM
Vale
R D
RD
Goldman
R D
RD
D000595:Amino Acid Sequence; D000818:Animals; D001370:Axonal Transport; D001369:Axons / Q000502:physiology*; D049832:Decapodiformes; D000939:Epitopes / Q000737:chemistry; D005455:Fluorescent Antibody Technique; D016547:Kinesins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D007700:Kinetics; D008870:Microtubules / Q000502:physiology*; D008969:Molecular Sequence Data; D016900:Neurofilament Proteins / Q000378:metabolism*; D021122:Protein Subunits; D021381:Protein Transport; D013997:Time Factors
D000939:Epitopes; D016900:Neurofilament Proteins; D021122:Protein Subunits; D016547:Kinesins