title: The relationship between relative solvent accessibility and evolutionary rate in protein evolution.
abstract: Recent work with Saccharomyces cerevisiae shows a linear relationship between the evolutionary rate of sites and the relative solvent accessibility (RSA) of the corresponding residues in the folded protein. Here, we aim to develop a mathematical model that can reproduce this linear relationship. We first demonstrate that two models that both seem reasonable choices (a simple model in which selection strength correlates with RSA and a more complex model based on RSA-dependent amino acid distributions) fail to reproduce the observed relationship. We then develop a model on the basis of observed site-specific amino acid distributions and show that this model behaves appropriately. We conclude that evolutionary rates are directly linked to the distribution of amino acids at individual sites. Because of this link, any future insight into the biophysical mechanisms that determine amino acid distributions will improve our understanding of evolutionary rates.
authors.affiliation: Center for Computational Biology and Bioinformatics, Institute for Cellular and Molecular Biology, University of Texas, Austin, Texas 78712, USA.
authors.forename: Duncan C
authors.initials: DC
authors.lastname: Ramsey
authors.forename: Michael P
authors.initials: MP
authors.lastname: Scherrer
authors.forename: Tong
authors.initials: T
authors.lastname: Zhou
authors.forename: Claus O
authors.initials: CO
authors.lastname: Wilke
mesh_terms: D000465:Algorithms; D000596:Amino Acids / Q000737:chemistry / Q000235:genetics; D003198:Computer Simulation; D030562:Databases, Protein; D019143:Evolution, Molecular; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D008956:Models, Chemical; D008957:Models, Genetic; D012441:Saccharomyces cerevisiae / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000235:genetics*; D012997:Solvents / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D029701:Saccharomyces cerevisiae Proteins; D012997:Solvents