水稻基因组物理图谱和遗传图谱的整合

水稻作为世界上最重要的粮食作物之一,与其它谷类作物有重要的同线性关系,是禾谷类植物的模式植物。国际水稻基因组测试项目(IRGSP)最近报道了覆盖率为95%、由389Mb组成的水稻基因组序列,实际上包括所有的常染色质和两个完整的着丝粒。总共37544个非转座的与蛋白质编码有关的基因已被鉴定,水稻基因组的绝大部分一般可通过DNA斑点杂交和电子杂交进行锚定,基因组测序数据也可整合到水稻的物理图谱中,物理图谱和遗传图谱的比较能够再现完整的水稻基因组的物理距离和遗传距离之间的关系。经常发现有细胞器基因转移到核内染色体上,水稻高分辨率的物理图谱的整合将很大地促进整个基因组的测序。今后物理图谱将有助于一些重要农艺性状的基因进行图位克隆,将作为禾本科植物基因组比较分析的一个重要工具。

An Intergrated Physical and Genetic Map of the Rice Genome

Rice,one of the most important food plants in the world,has significant syntenic relationships with the other cereal species and is a model plant for grasses.IRGSP has recently presented a map-based,finished quality sequence that covers 95% of the 389Mb genome,including virtually all of the euchromatin and two complete centromeres.A total of 37,544 non-transposable-element-related protein-coding genes have been identified.Most of the rice genome was anchored genetically by overgo hybridization,DNA gel blot hybridization,and in sillico anchoring.Genome sequencing data were integrated into the rice physical map.The comparison of the genetic and physical maps reveals the relationship of the genetic and physical distance in the whole rice genome.We have found the evidence for a widespread and recurrent gene transfer from the organelles to the nuclear chromosomes.The integrated high-resolution physical map of the rice genome will greatly facilitate the whole-genome sequencing.Furthermore,the physical map will be conductive to the map-based cloning of some important agronomical genes,and provide an important tool for the comparative analysis of grass genomes.