Nature Cell Biology5, 972 - 979 (2003)
Published online: 12 October 2003; | doi:10.1038/ncb1059
Actin filament uncapping localizes to ruffling lamellae and rocketing vesicles
Philip G. Allen
Hematology Division, Brigham and Women's Hospital and Harvard Medical School, Boston MA 02115, USA. pallen@rics.bwh.harvard.edu
Regulated actin filament assembly is critical for eukaryotic cell physiology. Actin filaments are polar structures1, and those with free high affinity or barbed ends are crucial for actin dynamics and cell motility2. Actin filament barbed-end-capping proteins inhibit filament elongation after binding3, and their regulated disassociation is proposed to provide a source of free filament ends to drive processes dependent on actin polymerization4. To examine whether dissociation of actin filament capping proteins occurs with the correct spatio-temporal constraints to contribute to regulated actin assembly in live cells, I measured the dissociation of an actin capping protein, gelsolin, from actin in cells using a variation of fluorescence resonance energy transfer (FRET). Uncapping was found to occur in cells at sites of active actin assembly, including protruding lamellae and rocketing vesicles, with the correct spatio-temporal properties to provide sites of actin filament polymerization during protrusion. These observations are consistent with models where uncapping of existing filaments provides sites of actin filament elongation.
MORE ARTICLES LIKE THIS
These links to content published by NPG are automatically generated
