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基因加倍(Geneduplication)被认为是进化的加速器。古老的基因组加倍事件已经在多个物种中被确定, 包括酵母、脊椎动物以及拟南芥等。本研究发现水稻基因组同样存在全基因组加倍事件,大概发生在禾谷类作物分化之前,距今约7000万年。在水稻基因组中,共找到117个加倍区段(Duplicatedblock),分布在水稻的全部12 条染色体,覆盖约60%的水稻基因组。在加倍区段,大约有20%的基因保留了加倍后的姊妹基因对(Duplicated pairs)。与此形成鲜明对照的是加倍区段的转录因子保留了60%的姊妹基因。禾本科植物全基因组加倍事件的确定对研究禾本科植物基因组的进化具有重要影响,暗示了多倍体化及随后的基因丢失、染色体重排等在禾谷类物种分化中扮演了重要角色。
Geneduplication is considered as an accelerator of evolution. Ancient genomic doubling events have been identified in several species, including yeast, vertebrates and Arabidopsis. In this study, genome-wide duplication event was also found in rice genome, which occurred approximately 70 million years ago before the differentiation of cereal crops. In the rice genome, a total of 117 Duplicated blocks were found, distributed in all 12 rice chromosomes, covering about 60% of the rice genome. In the doubled section, about 20% of the genes retained doubled pairs of Duplicated pairs. In stark contrast, the doubled segment of the transcription factor retains 60% of the sister genes. The determination of genome-wide doubling events in gramineous plants plays an important role in studying the evolution of gramineous genomes, suggesting that polyploidization and consequent loss of genes and chromosomal rearrangements play an important role in cereal species differentiation.