F-actin is the major component of muscle thin filaments and, more generally, of the microfilaments of the dynamic, multifunctional cytoskeletal systems of nonmuscle eukaryotic cells. Polymeric F-actin is formed by reversible noncovalent self-association of monomeric G-actin. To understand the dynamics of microfilament systems in cells, the dynamics of polymerization of pure actin must be understood. The following model has emerged from recent work. During the polymerization process, adenosine 5'-triphosphate (ATP) that is bound to G-actin is hydrolyzed to adenosine 5'-diphosphate (ADP) that is bound to F-actin. The hydrolysis reaction occurs on the F-actin subsequent to the polymerization reaction in two steps: cleavage of ATP followed by the slower release of inorganic phosphate (Pi). As a result, at high rates of filament growth a transient cap of ATP-actin subunits exists at the ends of elongating filaments, and at steady state a stabilizing cap of ADP.Pi-actin subunits exists at the barbed ends of filaments. Cleavage of ATP results in a highly stable filament with bound ADP.Pi, and release of Pi destabilizes the filament. Thus these two steps of the hydrolytic reaction provide potential mechanisms for regulating the monomer...Continue Reading
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alpha-crystallin stabilizes actin filaments and prevents cytochalasin-induced depolymerization in a phosphorylation-dependent manner
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Individual actin filaments in a microfluidic flow reveal the mechanism of ATP hydrolysis and give insight into the properties of profilin
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Formation of an actin-like filament concurrent with the enzymatic synthesis of inorganic polyphosphate
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A model of cell biological signaling predicts a phase transition of signaling and provides mathematical formulae
Mechanical fluctuations of the membrane-skeleton are dependent on F-actin ATPase in human erythrocytes
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An equilibrium model for the combined effect of macromolecular crowding and surface adsorption on the formation of linear protein fibrils
Cooperative supramolecular polymerization: comparison of different models applied on the self-assembly of bis(merocyanine) dyes
A central role for the WH2 domain of Srv2/CAP in recharging actin monomers to drive actin turnover in vitro and in vivo
Adenine and guanine nucleotide content of Triton-extracted cytoskeletal fractions of nonmuscle cells
The interplay between viscoelastic and thermodynamic properties determines the birefringence of F-actin gels
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Multiscale impact of nucleotides and cations on the conformational equilibrium, elasticity and rheology of actin filaments and crosslinked networks
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Glucose addiction of TSC null cells is caused by failed mTORC1-dependent balancing of metabolic demand with supply
The beta-thymosin/WH2 domain; structural basis for the switch from inhibition to promotion of actin assembly
Multiple-particle tracking measurements of heterogeneities in solutions of actin filaments and actin bundles
Force-induced dynamical properties of multiple cytoskeletal filaments are distinct from that of single filaments
Tight coupling of metabolic oscillations and intracellular water dynamics in Saccharomyces cerevisiae
Mechanism of GTP hydrolysis in tubulin polymerization: characterization of the kinetic intermediate microtubule-GDP-Pi using phosphate analogues
Kinetics of the interaction of a 41-kilodalton macrophage capping protein with actin: promotion of nucleation during prolongation of the lag period
Temperature-induced sol-gel transition and microgel formation in alpha -actinin cross-linked actin networks: A rheological study
Secondary structures in synthetic polypeptides from N-carboxyanhydrides: design, modulation, association, and material applications
Force-history dependence and cyclic mechanical reinforcement of actin filaments at the single molecular level
Proteomic characterization of harvested pseudopodia with differential gel electrophoresis and specific antibodies
Growth of tactoidal droplets during the first-order isotropic to nematic phase transition of F-actin
Detection of adenosine triphosphate through polymerization-induced aggregation of actin-conjugated gold/silver nanorods
β-Sheet to Helical-Sheet Evolution Induced by Topochemical Polymerization: Cross-α-Amyloid-like Packing in a Pseudoprotein with Gly-Phe-Gly Repeats.
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Smooth muscle proteins as intracellular components of the chromatophores of the Antarctic fishes Pagothenia borchgrevinki and Trematomus bernacchii (Nototheniidae)
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Flexibility of actin filaments derived from thermal fluctuations. Effect of bound nucleotide, phalloidin, and muscle regulatory proteins.
A mutation in an ATP-binding loop of Saccharomyces cerevisiae actin (S14A) causes a temperature-sensitive phenotype in vivo and in vitro.
Myopathy-Sensitive G-Actin Segment 227-235 Is Involved in Salt-Induced Stabilization of Contacts within the Actin Filament.
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