title: Long-range intra-protein communication can be transmitted by correlated side-chain fluctuations alone.
abstract: Allosteric regulation is a key component of cellular communication, but the way in which information is passed from one site to another within a folded protein is not often clear. While backbone motions have long been considered essential for long-range information conveyance, side-chain motions have rarely been considered. In this work, we demonstrate their potential utility using Monte Carlo sampling of side-chain torsional angles on a fixed backbone to quantify correlations amongst side-chain inter-rotameric motions. Results indicate that long-range correlations of side-chain fluctuations can arise independently from several different types of interactions: steric repulsions, implicit solvent interactions, or hydrogen bonding and salt-bridge interactions. These robust correlations persist across the entire protein (up to 60 Å in the case of calmodulin) and can propagate long-range changes in side-chain variability in response to single residue perturbations.
authors: Department of Chemistry, University of California at Berkeley, Berkeley, California, United States of America.
authors: Kateri H
authors: KH
authors: Dubay
authors: Jacques P
authors: JP
authors: Bothma
authors: Phillip L
authors: PL
authors: Geissler
mesh_terms: D000494:Allosteric Regulation; D001426:Bacterial Proteins / Q000737:chemistry; D001665:Binding Sites; D002147:Calmodulin / Q000737:chemistry; D019295:Computational Biology; D003198:Computer Simulation; D006860:Hydrogen Bonding; D008958:Models, Molecular; D009010:Monte Carlo Method; D019906:Nuclear Magnetic Resonance, Biomolecular; D017510:Protein Folding; D054730:Protein Interaction Domains and Motifs; D011506:Proteins / Q000737:chemistry*; D012997:Solvents
chemical_list: D001426:Bacterial Proteins; D002147:Calmodulin; D011506:Proteins; D012997:Solvents; C057438:barstar protein, Bacillus amyloliquefaciens