Adaptive selection and coevolution at the proteins of the @entity40607 repressive complexes in XXXX .

@entity71178 @entity40607 @entity71176 @entity71182 @entity71181 @entity71177 @entity71180 @entity71179 @entity238
UNASSIGNED: @entity40607 group (PcG) proteins are important epigenetic regulatory proteins that modulate the chromatin state through posttranslational histone modifications. These interacting proteins form multimeric complexes that repress gene expression. Thus, PcG proteins are expected to evolve coordinately, which might be reflected in their phylogenetic trees by concordant episodes of positive selection and by a correlation in evolutionary rates. In order to detect these signals of coevolution, the molecular evolution of 17 genes encoding the subunits of five @entity40607 repressive complexes has been analyzed in the @entity238 genus. The observed distribution of divergence differs substantially among and along proteins. Indeed, @entity71176 is uniformly conserved, whereas only the established protein domains are conserved in other proteins, such as PHO, @entity71177 , @entity71178 , @entity71179 and ASX. Moreover, regions with a low divergence not yet described as protein domains are present, for instance, in @entity71180 and @entity71181 . Maximum likelihood methods indicate an acceleration in the nonsynonymous substitution rate at the lineage ancestral to the obscura group species in most genes encoding subunits of the Pcl-PRC2 complex and in genes @entity71180 , @entity71178 and @entity71182 . These methods also allow inferring the action of positive selection in this lineage at genes E(z) and @entity71180 . Finally, the protein interaction network predicted from the complete proteomes of 12 @entity238 species using a coevolutionary approach shows two tight PcG clusters. These clusters include well-established binary interactions among PcG proteins as well as new putative interactions.Heredity advance online publication, 21 October 2015; doi:10.1038/hdy.2015.91.
