Key to Cytoskeletal Functions (1)Structure and Support (2)Intracellular Transport 3Contractility and Motility 4)Spatial Organization Actin filaments Actin filaments 11 (3) Motor protein Intermediate Microtubule 1 Intermediate filament f相aments Nerve cell Motor protein Actin filaments Microtubule (4) 2 Microtubule Motor protein ) (a) Epithelial cell (c) Dividing cell Copyright 1999 John Wiley and Sons,inc.All rights reservedThe three types of protein