Rapid movement of axonal neurofilaments interrupted by prolonged pauses.
Axonal cytoskeletal and cytosolic proteins are synthesized in the neuronal cell body and transported along axons by slow axonal transport, but attempts to observe this movement directly in living cells have yielded conflicting results. Here we report the direct observation of the axonal transport of neurofilament protein tagged with green fluorescent protein in cultured nerve cells. Live-cell imaging of naturally occurring gaps in the axonal neurofilament array reveals rapid, intermittent and highly asynchronous movement of fluorescent neurofilaments. The movement is bidirectional, but predominantly anterograde. Our data indicate that the slow rate of slow axonal transport may be the result of rapid movements interrupted by prolonged pauses.
Wang
L
L
Neuroscience Programme, Department of Biological Sciences, Ohio University, Athens, Ohio 45701, USA.
Ho
C L
CL
Sun
D
D
Liem
R K
RK
Brown
A
A
D000818:Animals; D000831:Animals, Newborn; D001370:Axonal Transport / Q000502:physiology*; D001369:Axons / Q000378:metabolism / Q000648:ultrastructure; D001692:Biological Transport / Q000502:physiology; D002478:Cells, Cultured; D015870:Gene Expression; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics; D008845:Microinjections; D008857:Microscopy, Interference / Q000379:methods; D016900:Neurofilament Proteins / Q000235:genetics / Q000378:metabolism*; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D017783:Superior Cervical Ganglion / Q000166:cytology; D013997:Time Factors; D014162:Transfection
D008164:Luminescent Proteins; D016900:Neurofilament Proteins; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins