Expression profiles in knock-down transgenic plants of high and low diversified duplicates in Arabidopsis thaliana

Duplicated genes comprise a various degree of functional diversification in plants. Previously, we identified 1,052 and 600 pairs of high and low diversified duplicates in Arabidopsis thaliana, respectively. Furthermore, we found single knock down of high diversified duplicates induces abnormal phenotypic change, while single knock down of low diversified duplicate does not induce abnormal phenotypic change due to functional compensation in the copy gene. Here, focusing on our identified two pairs of high and low diversified duplicates, we performed transcriptome analyses in each of knock down transgenic plants. Much of differential expressed genes from wild types were identified in knock down transgenic plants of both high and low diversified duplicates. Thus, functional compensation inferred by transcriptomics was similar in between high and low diversified duplicates. However, the trend of differentially expressed genes tend to be similar in a pair of low diversified duplicates but the similarity of expression profile was not observed in a pair of high diversified duplicates. This result suggests that a pair of low diversified duplicates tends to share similar functions but a pair of high diversified duplicates tends to undergo functional differences. We concluded that both high and low diversified duplicates play independent roles but the functional differences are quite low in a pair of low diversified duplicates.