Visualising the actin cytoskeleton

The actin cytoskeleton is a dynamic filamentous network whose formation and remodeling underlies the fundamental processes of cell motility and shape determination. To serve these roles, different compartments of the actin cy toskeleton engage in forming specific coupling sites between neighbouring c ells and with the underlying matrix, which themselves serve signal transduc ing functions. In this review, we focus on methods used to visualise the ac tin cytoskeleton and its dynamics; embracing the use of proteins tagged wit h conventional fluorophores and green fluorescent protein. Included also is a comparison of cooled CCD technology, confocal and 2-photon fluorescence microscopy of living and fixed cells, as well as a critique of current proc edures for electron microscopy. (C) 1999 Wiley-Liss, Inc.