State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Plant Commun. 2021 Dec 11;3(2):100268. doi: 10.1016/j.xplc.2021.100268. eCollection 2022 Mar 14.
Gene duplication provides raw genetic materials for evolution and potentially novel genes for crop improvement. The two seminal genomic studies of both mentioned the large number of genes independently duplicated in recent years, but the duplication mechanism and the evolutionary significance of these gene duplicates have not yet been investigated. Here, we found that a recent burst of gene duplications (hereafter abbreviated as the RBGD) has probably occurred in all sequenced Triticeae species. Further investigations of the characteristics of the gene duplicates and their flanking sequences suggested that transposable element (TE) activity may have been involved in generating the RBGD. We also characterized the duplication timing, retention pattern, diversification, and expression of the duplicates following the evolution of Triticeae. Multiple subgenome-specific comparisons of the duplicated gene pairs clearly supported extensive differential regulation and related functional diversity among such pairs in the three subgenomes of bread wheat. Moreover, several duplicated genes from the RBGD have evolved into key factors that influence important agronomic traits of wheat. Our results provide insights into a unique source of gene duplicates in Triticeae species, which has increased the gene dosage together with the two polyploidization events in the evolutionary history of wheat.
基因复制为进化提供了原始的遗传物质，并为作物改良提供了潜在的新基因。这两项开创性的基因组研究都提到了近年来大量独立复制的基因，但这些基因复制的机制和进化意义尚未得到研究。在这里，我们发现所有已测序的小麦族物种中可能都发生了近期基因复制的爆发（简称 RBGD）。对基因复制及其侧翼序列特征的进一步研究表明，转座元件（TE）的活性可能参与了 RBGD 的产生。我们还描述了在小麦族进化过程中，基因复制的时间、保留模式、多样化和表达情况。复制基因对在面包小麦三个亚基因组中的多个亚基因组特异性比较清楚地支持了这些基因对之间广泛的差异调控和相关功能多样性。此外，来自 RBGD 的几个复制基因已经进化成为影响小麦重要农艺性状的关键因素。我们的研究结果为小麦族物种中独特的基因复制源提供了深入了解，这些基因复制源增加了基因剂量，以及在小麦的进化历史中的两次多倍化事件。
