Coordinated Functional Divergence of Genes after Genome Duplication in Arabidopsis thaliana
First author:Riet De Smet; Affiliations: Ghent University(根特大学): Ghent, Belgium
Corresponding author:Yves Van de Peer
Gene and genome duplications have been rampant (猖獗的) during the evolution of flowering plants. Unlike small-scale gene duplications, whole-genome duplications (WGDs) copy entire pathways or networks, and as such create the unique situation in which such duplicated pathways or networks could evolve novel functionality through the coordinated sub- or neo-functionalization of its constituent genes. Here, we describe a remarkable case of coordinated gene expression divergence following WGDs in Arabidopsis thaliana. We identified a set of 92 homoeologous gene pairs that all show a similar pattern of tissue-specific gene expression divergence following WGD, with one homoeolog showing predominant expression in aerial tissues (地上部分组织) and the other homoeolog showing biased expression in tip-growth tissues (顶端生长组织). We provide evidence that this pattern of gene expression divergence seems to involve genes with a role in cell polarity (细胞极性) and that likely function in the maintenance of cell-wall integrity. Following WGD, many of these duplicated genes evolved separate functions through subfunctionalization in growth/development and stress response. Uncoupling these processes through genome duplications likely provided important adaptions with respect to growth and morphogenesis and defense against biotic and abiotic stress.