title: Modeling myosin-dependent rearrangement and force generation in an actomyosin network.
abstract: Actomyosin contractility is a major force-generating mechanism that drives rearrangement of actomyosin networks; it is fundamental to cellular functions such as cellular reshaping and movement. Thus, to clarify the mechanochemical foundation of the emergence of cellular functions, understanding the relationship between actomyosin contractility and rearrangement of actomyosin networks is crucial. For this purpose, in this study, we present a new particulate-based model for simulating the motions of actin, non-muscle myosin II, and α-actinin. To confirm the model's validity, we successfully simulated sliding and bending motions of actomyosin filaments, which are observed as fundamental behaviors in dynamic rearrangement of actomyosin networks in migrating keratocytes. Next, we simulated the dynamic rearrangement of actomyosin networks. Our simulation results indicate that an increase in the density fraction of myosin induces a higher-order structural transition of actomyosin filaments from networks to bundles, in addition to increasing the force generated by actomyosin filaments in the network. We compare our simulation results with experimental results and confirm that actomyosin bundles bridging focal adhesions and the characteristics of myosin-dependent rearrangement of actomyosin networks agree qualitatively with those observed experimentally.
authors.affiliation: Institute for Frontier Medical Sciences, Kyoto University, Shogoinkawaharacho 6068507, Kyoto, Japan. inoue@frontier.kyoto-u.ac.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Inoue
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Tsuda
authors.forename: Koji
authors.initials: K
authors.lastname: Nakagawa
authors.forename: Masaki
authors.initials: M
authors.lastname: Hojo
authors.forename: Taiji
authors.initials: T
authors.lastname: Adachi
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism; D000185:Actinin / Q000378:metabolism; D000205:Actomyosin / Q000378:metabolism*; D001696:Biomechanical Phenomena / Q000502:physiology; D003198:Computer Simulation; D003432:Cross-Linking Reagents / Q000378:metabolism; D008954:Models, Biological; D009119:Muscle Contraction / Q000502:physiology; D009218:Myosins / Q000378:metabolism*
chemical_list: D003432:Cross-Linking Reagents; D000185:Actinin; D000205:Actomyosin; D009218:Myosins