Evolutionary transcriptomics unveils rapid changes of gene expression patterns in flowering plants

The evolutionary history of angiosperms (flowering plants) is characterized by a highly accelerated rate of diversification. Although a number of hypotheses have been proposed to explain the ecological success and rapid rise of angiosperms, the molecular mechanisms underlying their speciation are only partially understood. In this study, we analyzed the developmental transcriptomes of seven angiosperm species spanning 160 million years of evolution. We demonstrate that angiosperm protein-coding gene expression patterns diverged rapidly. Particularly high rates of expression changes were found for genes that are involved in the response to endogenous and environmental stimuli, promoting broad ecological tolerances, adaptive evolution, and speciation. This study highlights how ecological and evolutionary dynamics are highly interrelated, shows that the rates of expression divergence differ from those previously described for mammals, and provides a comprehensive resource to perform cross-kingdom comparative studies of transcriptome evolution.