title: Computational model of polarized actin cables and cytokinetic actin ring formation in budding yeast.
abstract: The budding yeast actin cables and contractile ring are important for polarized growth and division, revealing basic aspects of cytoskeletal function. To study these formin-nucleated structures, we built a three-dimensional (3D) computational model with actin filaments represented as beads connected by springs. Polymerization by formins at the bud tip and bud neck, crosslinking, severing, and myosin pulling, are included. Parameter values were estimated from prior experiments. The model generates actin cable structures and dynamics similar to those of wild type and formin deletion mutant cells. Simulations with increased polymerization rate result in long, wavy cables. Simulated pulling by type V myosin stretches actin cables. Increasing the affinity of actin filaments for the bud neck together with reduced myosin V pulling promotes the formation of a bundle of antiparallel filaments at the bud neck, which we suggest as a model for the assembly of actin filaments to the contractile ring.
authors.affiliation: Department of Physics, Lehigh University, Bethlehem, Pennsylvania, 18105, USA.
authors.forename: Haosu
authors.initials: H
authors.lastname: Tang
authors.affiliation: Department of Physics, Lehigh University, Bethlehem, Pennsylvania, 18105, USA.
authors.forename: Tamara C
authors.initials: TC
authors.lastname: Bidone
authors.affiliation: Department of Physics, Lehigh University, Bethlehem, Pennsylvania, 18105, USA.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Vavylonis
mesh_terms: D008841:Actin Cytoskeleton / Q000502:physiology; D000199:Actins / Q000737:chemistry*; D003198:Computer Simulation; D048749:Cytokinesis / Q000502:physiology*; D005656:Fungal Proteins / Q000502:physiology; D017353:Gene Deletion; D021621:Imaging, Three-Dimensional; D024701:Myosin Type V / Q000737:chemistry; D009218:Myosins / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000166:cytology; D004718:Saccharomycetales / Q000166:cytology*
chemical_list: D000199:Actins; D005656:Fungal Proteins; D024701:Myosin Type V; D009218:Myosins
keywords: actin cables; budding yeast; computational model; contractile ring