Peking Univ, Ctr Bioinformat, Natl Lab Plant Genet Engn & Prot Engn, Coll Life Sci, Beijing 100871, Peoples R China; Chinese Acad Sci, Ctr Gen & Bioinformat, Beijing Gen Inst, Beijing 101300, Peoples R China; Hebei Polytech Univ, Coll Math, Tangshan 063009, Hebei, Peoples R China; Chinese Acad Sci, Inst Bot, Lab Systemat & Evolutionary Bot, Beijing 100093, Peoples R China; Acad Sinica, Inst Theoret Phys, Beijing 100080, Peoples R China
英文摘要:
Large-scale duplication events have been recently uncovered in the rice genome, but different interpretations were proposed regarding the extent of the duplications. Through analysing the 370 AAb genome sequences assembled into 12 chromosomes of Oryza sativa subspecies indica, we detected 10 duplicated blocks on all 12 chromosomes that contained 47% of the total predicted genes. Based on the phylogenetic analysis, we inferred that this was a result of a genome duplication that occurred c. 70 million years ago, supporting the polyploidy origin of the rice genome. In addition, a segmental duplication was also identified involving chromosomes 11 and 12, which occurred c. 5 million years ago. Following the duplications, there have been large-scale chromosomal rearrangements and deletions. About 30-65% of duplicated genes were lost shortly after the duplications, leading to a rapid diploidization. Together with other lines of evidence, we propose that polyploidzation is still an ongoing process in grasses of polyploidy origins.
Wang, XY,Shi, XL,Hao, BL,et al. Duplication and DNA segmental loss in the rice genome: implications for diploidization[J]. NEW PHYTOLOGIST,2005,165(3):937-946.
