noun, plural: microfilaments
A thin, helical, single-stranded filament of the cytoskeleton found in the cytoplasm of eukaryotic cells, composed of actin subunits, and functions primarily in maintaining the structural integrity of a cell and cell movements.
Additionally, the microfilament:
- provides mechanical support for the cell or maintain structural integrity of the cell by forming a Band just beneath the cell membrane
- participates in certain cell junctions; link transmembrane proteins (e.g., cell surface receptors) to cytoplasmic proteins
- anchors the centrosomes at opposite poles of the cell during mitosis; aids in the contraction of the cell during cytokinesis
- generates cytoplasmic streaming (i.e. Intracellular movement, or the flowing of cytoplasm within cells)
- enables cell locomotion(through lamellipodia, filopodia, or pseudopodia)
- interacts with myosin ("thick") filaments in skeletal muscle fibers to provide the force of muscular contraction.
Word origin: Gk: comb. form repr. mīkrós, small + NL fīlāmentum, equiv. to LL fīlā(re), to wind thread, spin.
Related forms: microfilamentous (adjective).