Myosin with two FERM domains in the tail region. It has an extended lever arm consisting of five calmodulin binding IQ motifs followed by a single alpha helix (SAH). Myosin VII is required for phagocytosis in "Dictyostelium discoideum", spermatogenesis in "C. elegans" and stereocilia formation in mice and zebrafish. Myosin VIII is a plant-specific myosin linked to cell division; specifically, it is involved in regulating the flow of cytoplasm between cells and in the localization of vesicles to the phragmoplast. Myosin IX is a group of single-headed motor proteins. It was first shown to be minus-end directed, but a later study
Myosin cells, the long coiled-coil tails of the individual myosin molecules join together, forming the thick filaments of the sarcomere. The force-producing head domains stick out from the side of the thick filament, ready to walk along the adjacent actin-based thin filaments in response to the proper chemical signals. Myosin III is a poorly understood member of the myosin family. It has been studied "in vivo" in the eyes of "Drosophila", where it is thought to play a role in phototransduction. A human homologue gene for myosin III, MYO3A, has been uncovered through the Human Genome Project and is expressed in