The structure of an open state of beta-actin at 2.65 A resolution.

  title={The structure of an open state of beta-actin at 2.65 A resolution.},
  author={John K Chik and Uno Lindberg and Clarence Schutt},
  journal={Journal of molecular biology},
  volume={263 4},
The structure of an "open state" of crystalline profilin:beta-actin has been solved to 2.65 A by X-ray crystallography. The open-state crystals, in 1.8 M potassium phosphate, have an expanded unit cell dimension in the c direction of 185.7 A compared with 171.9 A in the previously solved ammonium sulphate-stabilized "tight-state" structure. The unit cell change between the open and the tight states is accompanied by large subdomain movements in actin. Furthermore, the nucleotide in the open… 

The open nucleotide pocket of the profilin/actin x-ray structure is unstable and closes in the absence of profilin.

Molecular dynamics simulations are used to model the thermodynamic properties of the actin x-ray structure, outside the crystal lattice, in an aqueous environment with profilin removed, and show that the open-nucleotide-pocket, Profilin-free structure is actually unstable, and closes.

Crystal Structure of Monomeric Actin in the ATP State

The x-ray crystal structure of tetramethylrhodamine-5-maleimide-actin with bound AMPPNP, a non-hydrolyzable ATP analog, was determined and an analysis of the existing structures of members of the actin superfamily suggests that the cleft is open in the nucleotide-free state.

ATPase activity and conformational changes in the regulation of actin.

  • H. Schüler
  • Chemistry, Biology
    Biochimica et biophysica acta
  • 2001

Structure and dynamics of calmodulin in solution.

Crystal Structures of Expressed Non-polymerizable Monomeric Actin in the ADP and ATP States*

This work expressed a cytoplasmic actin in Sf9 cells, which was rendered non-polymerizable by virtue of two point mutations in subdomain 4 (A204E/P243K), and suggests that the nucleotide-dependent formation of the D-loop helix may result from signal propagation through crystal packing interactions.

The crystal structure of a cross-linked actin dimer suggests a detailed molecular interface in F-actin.

A plausible model of F-actin can be constructed by reintroducing the known filament twist, without disturbing significantly the interface observed in the actin dimer crystal.

Solution properties of tetramethylrhodamine-modified G-actin.




Structural dynamics of F-actin: I. Changes in the C terminus.

Three-dimensional reconstructions from electron micrographs show that a bridge of density exists between the two strands of the filament in Ca(2+)-actin that is absent in Mg(2)+-actin, and may be induced by myosin binding, since this movement generates changes in actin's diffraction that are very similar to the changes in the muscle X-ray pattern during activation.

Structural studies on the ribbon-to-helix transition in profilin: actin crystals.

A preliminary comparison of two states of profilin:beta-actin crystals shows that crystal polymorphism involves movements of actin subdomains at hinge points homologous to those found in hexokinase, a protein whose polypeptide fold is related to actin.

Crystallization and structure determination of bovine profilin at 2.0 A resolution.

The polypeptide fold of bovine profilin is generally similar to those observed by NMR forprofilin from other sources, although the N terminus of Acanthamoeba profilIn isoform I lies in a distorted helix and the C-terminal helix is less tilted with respect to the strands in the central beta-pleated sheet than is observed in bovin profil in.

Atomic structure of the actin: DNase I complex

The atomic models of the complex between rabbit skeletal muscle actin and bovine pancreatic deoxyribonuclease I both in the ATP and ADP forms have been determined byo X-ray analysis at an effective

Structural basis for the destabilization of F-actin by phosphate release following ATP hydrolysis.

The structure of crystalline profilin–β-actin

The three-dimensional structure of bovine profilin–β-actin has been solved to 2.55 Å resolution by X-ray crystallography and appears to correspond to the solution contact in vitro.

Removing the two C-terminal residues of actin affects the filament structure.

Long-range conformational effects of proteolytic removal of the last three residues of actin.

It has been concluded that perturbation of the C-terminal structure in monomeric actin is transmitted to the cleft, where nucleotide and bivalent cation are bound, and to the DNAse-I binding loop on the top of subdomain 2.

The actin fold

  • W. KabschK. Holmes
  • Biology
    FASEB journal : official publication of the Federation of American Societies for Experimental Biology
  • 1995
X‐ray structure analysis of actin and of the NH2‐terminal domain of the heat‐shock cognate protein Hsc70 has revealed an unexpected extensive structural similarity between these two molecules, suggesting that the molecules may have evolved by gene duplication.