title: Biphasic targeting and cleavage furrow ingression directed by the tail of a myosin II.
abstract: Cytokinesis in animal and fungal cells utilizes a contractile actomyosin ring (AMR). However, how myosin II is targeted to the division site and promotes AMR assembly, and how the AMR coordinates with membrane trafficking during cytokinesis, remains poorly understood. Here we show that Myo1 is a two-headed myosin II in Saccharomyces cerevisiae, and that Myo1 localizes to the division site via two distinct targeting signals in its tail that act sequentially during the cell cycle. Before cytokinesis, Myo1 localization depends on the septin-binding protein Bni5. During cytokinesis, Myo1 localization depends on the IQGAP Iqg1. We also show that the Myo1 tail is sufficient for promoting the assembly of a "headless" AMR, which guides membrane deposition and extracellular matrix remodeling at the division site. Our study establishes a biphasic targeting mechanism for myosin II and highlights an underappreciated role of the AMR in cytokinesis beyond force generation.
authors.affiliation: Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Fang
authors.forename: Jianying
authors.initials: J
authors.lastname: Luo
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Nishihama
authors.forename: Carsten
authors.initials: C
authors.lastname: Wloka
authors.forename: Christopher
authors.initials: C
authors.lastname: Dravis
authors.forename: Mirko
authors.initials: M
authors.lastname: Travaglia
authors.forename: Masayuki
authors.initials: M
authors.lastname: Iwase
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Vallen
authors.forename: Erfei
authors.initials: E
authors.lastname: Bi
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism; D000199:Actins / Q000378:metabolism; D000205:Actomyosin / Q000378:metabolism*; D002453:Cell Cycle / Q000502:physiology; D048749:Cytokinesis / Q000502:physiology*; D007700:Kinetics; D018995:Myosin Heavy Chains / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D018994:Myosin Light Chains / Q000235:genetics; D015879:Myosin Subfragments / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D011485:Protein Binding / Q000502:physiology; D054730:Protein Interaction Domains and Motifs / Q000502:physiology; D020836:Protein Structure, Quaternary; D021381:Protein Transport / Q000502:physiology; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D012441:Saccharomyces cerevisiae / Q000502:physiology; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D020703:ras GTPase-Activating Proteins / Q000235:genetics
chemical_list: D000199:Actins; C466084:BNI5 protein, S cerevisiae; C101203:IQ motif containing GTPase activating protein 1; C113979:MLC1 protein, S cerevisiae; C112936:MYO1 protein, S cerevisiae; D018994:Myosin Light Chains; D015879:Myosin Subfragments; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D020703:ras GTPase-Activating Proteins; D000205:Actomyosin; D018995:Myosin Heavy Chains