The actin cytoskeleton
The actin cytoskeleton consists of microfilaments (or actin filaments) which are the thinnest filaments of the cytoskeleton found in the cytoplasm of all eukaryotic cells. These linear polymers of actin subunits are flexible and relatively strong, resisting buckling by multi-piconewton compressive forces and filament fracture by nanonewton tensile forces. Microfilaments are highly versatile, functioning in (a) actin-driven expansion, where each elongating filament harnesses the hydrolysis energy of its "on-board" ATP to propel cell crawling, ameboid movement, and changes in cell shape, and (b) actomyosin-driven contractile molecular motors, where the thin filaments serve as tensile platforms for myosin's ATP hydrolysis-dependent pulling action in muscle contraction and uropod advancement.
Confocal laser scanning microscopy