Uozu S, Ikehashi H, Ohmido N, Ohtsubo H, Ohtsubo E, Fukui K
Laboratory of Rice Genetic Engineering, Hokuriku National Agricultural Experiment Station, Joetsu, Japan.
Plant Mol Biol. 1997 Dec;35(6):791-9. doi: 10.1023/a:1005823124989.
Large variation in genome size as determined by the nuclear DNA content and the mitotic chromosome size among diploid rice species is revealed using flow cytometry and image analyses. Both the total chromosomal length (r = 0.939) and the total chromosomal area (r = 0.927) correlated well with the nuclear DNA content. Among all the species examined, Oryza australiensis (E genome) and O. brachyantha (F genome), respectively, were the largest and smallest in genome size. O. sativa (A genome) involving all the cultivated species showed the intermediate genome size between them. The distribution patterns of genome-specific repetitive DNA sequences were physically determined using fluorescence in situ hybridization (FISH). O. brachyantha had limited sites of the repetitive DNA sequences specific to the F genome. O. australiensis showed overall amplification of genome-specific DNA sequences throughout the chromosomes. The amplification of the repetitive DNA sequences causes the variation in the chromosome morphology and thus the genome size among diploid species in the genus Oryza.
利用流式细胞术和图像分析揭示了二倍体水稻物种中由核DNA含量和有丝分裂染色体大小所决定的基因组大小的巨大差异。总染色体长度（r = 0.939）和总染色体面积（r = 0.927）均与核DNA含量高度相关。在所研究的所有物种中，澳洲稻（E基因组）和短药野生稻（F基因组）的基因组大小分别最大和最小。包含所有栽培种的栽培稻（A基因组）的基因组大小介于二者之间。利用荧光原位杂交（FISH）从物理层面确定了基因组特异性重复DNA序列的分布模式。短药野生稻中F基因组特异性重复DNA序列的位点有限。澳洲稻在整个染色体上显示出基因组特异性DNA序列的整体扩增。重复DNA序列的扩增导致了染色体形态的变化，进而导致了稻属二倍体物种间基因组大小的差异。
