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水稻所在的稻属(Oryza)共有24个左右的物种。由于野生稻含有大量的优良农艺性状基因,在水稻遗传学研究中日益受到重视。随着国际稻属基因组计划的开展,越来越多的稻属基因组序列被测定,稻属成为进行比较、功能和进化基因组学研究的模式系统。近期开展的一系列研究对稻属不同基因组区段以及全基因组序列的比较分析,揭示了稻属在基因组大小、基因移动、多倍体进化、常染色质到异染色质的转化以及着丝粒区域的进化等方面的分子机制。转座子的活性以及转座子因非均等重组或非法重组而造成的删除,对稻属基因组的扩增和收缩具有重要作用。DNA双链断裂修复介导的基因移动,特别是非同源末端连接,是稻属基因组非共线性基因形成的主要来源。稻属基因组从常染色质到异染色质的转换过程,伴随着转座子的大量扩增、基因片段的区段性和串联重复以及从基因组其他位置不断捕获异染色质基因。对稻属不同物种间基因拷贝数、特异基因和重要农艺性状基因的进化等研究,可揭示稻属不同物种间表型和适应性差异的分子基础,将加速水稻的育种和改良。
There are about 24 species of Oryza where the rice is located. Since wild rice contains a large number of excellent agronomic traits, it has been paid more and more attention in the research of rice genetics. With the development of the International Rice Genome Project, more and more genomes of the genus Oryza were sequenced and the genus Oryza was the model system for comparative, functional and evolutionary genomics research. A series of recent studies comparing different genomic regions and genome-wide sequences of the genus Oryza reveals that genomic size, gene movement, polyploid evolution, and the conversion of euchromatin to heterochromatin and centromere Regional evolution and other aspects of the molecular mechanism. The activity of transposons and the deletion of transposons due to non-equal recombination or illegal recombination play an important role in the amplification and contraction of the genome of the genus Oryza. DNA double-strand break repair mediated gene movement, especially non-homologous end-joining, is the main source of the non-lineal gene formation in the genome of the genus Oryza. The transformation of the genome of the genus Orycota from euchromatin to heterochromatin, accompanied by extensive amplification of transposons, segmental and tandem duplication of genes, and continuous capture of heterochromatin genes from elsewhere in the genome. Studies on gene copy number, specific genes and important agronomic traits among different species of Oxya can reveal the molecular basis of differences in phenotype and adaptability among different species of Oryza, which will accelerate the breeding and improvement of rice.