title: Understanding the cooperative interaction between myosin II and actin cross-linkers mediated by actin filaments during mechanosensation.
abstract: Myosin II is a central mechanoenzyme in a wide range of cellular morphogenic processes. Its cellular localization is dependent not only on signal transduction pathways, but also on mechanical stress. We suggest that this stress-dependent distribution is the result of both the force-dependent binding to actin filaments and cooperative interactions between bound myosin heads. By assuming that the binding of myosin heads induces and/or stabilizes local conformational changes in the actin filaments that enhances myosin II binding locally, we successfully simulate the cooperative binding of myosin to actin observed experimentally. In addition, we can interpret the cooperative interactions between myosin and actin cross-linking proteins observed in cellular mechanosensation, provided that a similar mechanism operates among different proteins. Finally, we present a model that couples cooperative interactions to the assembly dynamics of myosin bipolar thick filaments and that accounts for the transient behaviors of the myosin II accumulation during mechanosensation. This mechanism is likely to be general for a range of myosin II-dependent cellular mechanosensory processes.
authors.affiliation: Department of Cell Biology, The Johns Hopkins University, Baltimore, Maryland, USA. tzluo@jhu.edu
authors.forename: Tianzhi
authors.initials: T
authors.lastname: Luo
authors.forename: Krithika
authors.initials: K
authors.lastname: Mohan
authors.forename: Vasudha
authors.initials: V
authors.lastname: Srivastava
authors.forename: Yixin
authors.initials: Y
authors.lastname: Ren
authors.forename: Pablo A
authors.initials: PA
authors.lastname: Iglesias
authors.forename: Douglas N
authors.initials: DN
authors.lastname: Robinson
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism*; D000199:Actins / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000378:metabolism*; D004023:Dictyostelium / Q000166:cytology / Q000378:metabolism; D007700:Kinetics; D040542:Mechanotransduction, Cellular; D008840:Microfilament Proteins / Q000378:metabolism*; D008954:Models, Biological; D009010:Monte Carlo Method; D024462:Myosin Type II / Q000378:metabolism*; D011485:Protein Binding; D015800:Protozoan Proteins / Q000378:metabolism*; D013314:Stress, Mechanical
chemical_list: D000199:Actins; D003432:Cross-Linking Reagents; D008840:Microfilament Proteins; D015800:Protozoan Proteins; C101109:ctxA protein, Dictyostelium discoideum; D024462:Myosin Type II