Crosslinkers - long molecules. Found in bundles in microvilli of brush border, Limulus sperm, and Drosophila ooctyes. Model for Extension of a Cell Process Chemotaxis by neutrophils or amoeba. Receptors for chemotactic factors. Release monomers from buffered pool.
Monomers add to free barbed ends.
Barbed ends ultimately capped. Cofilin severs filaments to cause depolymerization proximally. Non-muscle Myosin Many types of myosin exist. All have a characteristic motor domain. The motor domain has actin-activated ATPase, can move actin filaments, and has a characteristic amino acid sequence.