Biphasic targeting of Myo1 and the guiding role of the actomyosin ring in membrane deposition and ECM remodeling during cytokinesis. (A) A model for the biphasic targeting of Myo1 during the cell cycle. Myo1 targeting before cytokinesis is mediated solely by the septin-binding protein Bni5. Myo1 targeting during cytokinesis depends on Mlc1 and Iqg1. Iqg1, Myo1, and actin filaments at the bud neck likely define the minimal components of the AMR. (B) A model for the guiding role of the AMR in PS formation. In addition to force generation, the AMR may function as a “compass” to guide membrane deposition and ECM remodeling (PS formation in yeast) during cytokinesis by capturing and distributing vesicles and their cargoes along the division site. This motor-independent guidance role of the AMR is sufficient to ensure membrane closure during cytokinesis for small cells such as budding yeast, but not for the larger ones such as fission yeast and animal cells.