杂交水稻及其“三系”线粒体DNA的AP-PCR指纹图谱

MITOCHONDRIAL GENOME FINGERPRINTING IN HYBRID RICE AND ITS ASSOCIATED LINES USING THE PRIMED POLYMERASE CHAIN REACTION

为了研究水稻（Ｏｒｙｚａ ｓａｔｉｖａ Ｌ．）细胞质雄性不育（ＣＭＳ）与线粒体基因组的关系，应用ＡＰ－ＰＣＲ 分析，用７ 个任意单引物对６ 种水稻品系线粒体ＤＮＡ 进行了扩增。水稻线粒体ＤＮＡ 的ＡＰ－ＰＣＲ 产物可分为三种类型：（１）所有供试品系均能扩增的片段，它们代表了线粒体ＤＮＡ 在进化上的保守性序列。有４ 个引物检测到这类片段。（２）２ 个以上水稻品系共同出现而在全部供试材料间存在差异的扩增片段，这类片段是检测水稻线粒体ＤＮＡ多态性的主要来源。（３）一种细胞质类型所特有的扩增片段，从引物Ｒ２ 和Ｖ５ 的扩增产物中发现了这类片段，它们可能与ＣＭＳ有关联。另外，ＷＡ型不育系珍汕９７Ａ 与其杂种之间在６ 个引物的扩增图谱上均存在不同程度的差异。

A new economic and efficient DNA polymorphism assay was developed in 1990 that is based on the amplification by polymerase chain reaction (PCR) of random DNA segments using primers of arbitrary nucleotide sequence. Authors have now adapted this type of amplification to rice mitochondrial genome. Using 6 rice varieties in conjunction with 7 of 20—27 mer oligonucleotide primers, the AP PCR products revealed that the amplified DNA bands fell into two categories, the evolutively conserved the cytoplasmic specific. It is suggested that AP PCR assay of mtDNA may help to classfy or identify the cytoplasms in rice. By comparing“fingerprints”among the WA type Cytoplasmic male sterility (CMS) rice, its Maintainer and Restorer lines, as well as its hybrid, one CMS cytoplasm specific band (primer R 2/630 bp) and one normal cytoplasm specific segment (primer V 5/707 bp) could be directly identified among the set of amplified DNA fragments. Further, some difference in the amplification patterns of mtDNA between CMS line and its hybrid, which infers that rearrangement of mitochondrial genome in hybrid rice probably happened.