Positive selection and ancient duplications in the evolution of class B floral homeotic genes of orchids and grasses.

ABSTRACT:

Background

Positive selection is recognized as the prevalence of nonsynonymous over synonymous substitutions in a gene. Models of the functional evolution of duplicated genes consider neofunctionalization as key to the retention of paralogues. For instance, duplicate transcription factors are specifically retained in plant and animal genomes and both positive selection and transcriptional divergence appear to have played a role in their diversification. However, the relative impact of these two factors has not been systematically evaluated. Class B MADS-box genes, comprising DEF-like and GLO-like genes, encode developmental transcription factors essential for establishment of perianth and male organ identity in the flowers of angiosperms. Here, we contrast the role of positive sele

SUBMITTER: Mondragon-Palomino M 

PROVIDER: S-EPMC2680841 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature