On the cytomechanics and fluid dynamics of growth cone motility.
Following a brief review of the controversy concerning the physical mechanism of growth cone advance, we present cytomechanical data to support a version of the classic model of growth cone motility. In this model, the growth cone is pulled forward by filopodial tension. Observations of growth cone behavior and axonal guidance suggest that this model should include fluid flow mechanisms as well as the original solid, elastic mechanism. Recent data are reviewed on the similarity of the fluid behavior of cytoplasm and of suspensions of cytoskeletal filaments. The thixotropic behavior of cytoplasm is used to develop a model for lamellipodial protrusion caused by filopodial tension.
Heidemann
S R
SR
Department of Physiology, Michigan State University, East Lansing 48824-1101.
Lamoureux
P
P
Buxbaum
R E
RE
D008841:Actin Cytoskeleton / Q000502:physiology; D000818:Animals; D001826:Body Fluids / Q000502:physiology; D002455:Cell Division; D002465:Cell Movement; D003593:Cytoplasm / Q000502:physiology; D006801:Humans; D008959:Models, Neurological; D016501:Neurites / Q000502:physiology*