Filopodia: molecular architecture and cellular functions

Filopodia are thin, actin-rich, finger-like structures that are involved in numerous cellular processes, such as cell migration, wound healing, neurite outgrowth and embryonic development. But what are the mechanisms that regulate filopodia formation in distinct cell types? Filopodia are thin, actin-rich plasma-membrane protrusions that function as antennae for cells to probe their environment. Consequently, filopodia have an important role in cell migration, neurite outgrowth and wound healing and serve as precursors for dendritic spines in neurons. The initiation and elongation of filopodia depend on the precisely regulated polymerization, convergence and crosslinking of actin filaments. The increased understanding of the functions of various actin-associated proteins during the initiation and elongation of filopodia has provided new information on the mechanisms of filopodia formation in distinct cell types.