Required for contractile events in embryos that occur prior to mitosis, such as cortical ruffling and pseudocleavage. Promotes membrane ruffling by organizing cortical patches of septins and myosin II. Not generally required for cytokinesis in mitotic cells. Required for the asymmetric cleavage events that extrude the two polar bodies during oocyte meiosis. Not required for meiotic contractile ring assembly, initiation or closure but is required for the transformation of the contractile ring from a disk above the spindle to a tube around the spindle midzone. Promotes astral microtubule-directed cortical myosin polarization and cleavage furrow ingression. Regulates neuroblast cytokinesis during mid- to late-embryogenesis and is required for ventral enclosure. Strongly expressed in dividing neuroblasts under the ventral epidermal cells during ventral enclosure. Enriched in embryos, where it localizes predominantly to cortical regions and the cytokinetic furrow in telophase. RNAi-mediated knockdown of the protein causes 100% embryonic lethality. Abnormal polar body extrusion with large and unstable polar bodies that often fuse with the oocyte. Failure of contractile ring to transform from a disk to a tube during meiosis. Ventral enclosure defects and failure of neuroblasts to complete cytokinesis. Aberrant microtubule-directed cortical myosin polarization.