GFP ILLUMINATES THE CYTOSKELETON

Until recently, cytoskeleton research has relied primarily on immunofl uorescence microscopy techniques, requiring fixation and hence killing of the specimen before the analysis. The sole method for visualizing cytoskeletal dynamics in living cells has been tile microinjection of purified and fluorescently labelled protein, brit technical difficulti es have precluded its widespread use. The recent introduction of green fluorescent protein (GFP) has enabled visualization of proteins and c ytoskeletal dynamics with only minimal perturbations of the living cel l and has opened new horizons for studying the cytoskeleton.