Format

Send to

Choose Destination
Biophys J. 2005 Jul;89(1):167-78. Epub 2005 May 6.

Probing the local dynamics of nucleotide-binding pocket coupled to the global dynamics: myosin versus kinesin.

Author information

1
Laboratory of Computational Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA. zhengwj@helix.nih.gov

Abstract

Based on the elastic network model, we develop a new analysis for protein complexes, which probes the local dynamics of a subsystem that is elastically coupled to a fluctuating environment. This method is applied to a comparative dynamical analysis of the nucleotide-binding pocket of two motor proteins-myosins and kinesins. In myosins, the observed structural changes in the nucleotide-pocket from the transition state to the rigorlike state are dominated by the lowest normal mode that involves significant movements in both switch I and switch II; in kinesins, the measured conformational changes in the nucleotide-pocket are also dominated by the lowest mode, which, however, only involves large movement in switch I. We then compute the global structural changes induced by the nucleotide-pocket deformations as described by the dominant pocket-mode, which yield encouraging results: in myosins, multiple hinge motions involving the opening/closing of the cleft between the upper and lower 50 -kDa subdomains and the swinging movement of the converter are induced, which are dominated by precisely the same global mode that has been recently identified by us as important to the dynamical correlations among the nucleotide-pocket, the actin-binding site, and the converter; in kinesins, the induced global conformational changes are well described by a highly collective global mode which hints for a dynamical pathway spanning from the nucleotide-pocket to the neck-linker via the H6 helix.

PMID:
15879477
PMCID:
PMC1366515
DOI:
10.1529/biophysj.105.063305
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center