Functional cooperation between the microtubule and actin cytoskeletons

In diverse cell types, microtubule (MT) and actin filament networks coopera te functionally during a wide variety of processes, including vesicle and o rganelle transport, cleavage furrow placement, directed cell migration, spi ndle rotation, acid nuclear migration. The mechanisms by which MTs and acti n filaments cooperate to mediate these different processes can be grouped i nto two broad categories: coordinated MT- and actin-based transport to move vesicles, organelles, and cell fate determinants; and targeting and captur e of MT ends at cortical actin sites. Over the past several years, a growin g number of cellular factors that bridge these cytoskeletal systems have be en identified. These include 'hetero-motor' complexes (physically associate d myosin and kinesin), myosin-CLIP170 complexes, formin homology (FH) prote ins, dynein and the dynactin complex, Kar9p, coronin, Kelch repeal containi ng proteins, and ERM proteins.