Differential requirements for mRNA folding partially explain why highly expressed proteins evolve slowly.

ABSTRACT: The cause of the tremendous among-protein variation in the rate of sequence evolution is a central subject of molecular evolution. Expression level has been identified as a leading determinant of this variation among genes encoded in the same genome, but the underlying mechanisms are not fully understood. We here propose and demonstrate that a requirement for stronger folding of more abundant mRNAs results in slower evolution of more highly expressed genes and proteins. Specifically, we show that: (i) the higher the expression level of a gene, the greater the selective pressure for its mRNA to fold; (ii) random mutations are more likely to decrease mRNA folding when occurring in highly expressed genes than in lowly expressed genes; and (iii) amino acid substitution rate is negatively corre

SUBMITTER: Park C 

PROVIDER: S-EPMC3581962 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature