MOLECULAR MOTORS AND CELL MOTILITY IN THE BRAIN

The advent of video computer-enhanced microscopy has provided a new vi sion of cell migrations, growth cones, and fast axonal transport in th e nervous system. In images obtained in studies of fast transport in i solated axoplasm from the squid giant axon, a virtual torrent of membr ane traffic could be seen moving in both directions. Similarly, examin ation of growth cones and cell migrations in vitro and in vivo reveale d properties of cell motility that were previously unsuspected. Eviden ce has accumulated that many of these activities are driven by a varie ty of microtubule and microfilament based motors.