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作 者 ：魏磊;严志祥;余金洪;丁毅

期 刊 ：武汉植物学研究 2008年 26卷 6期 页码：567-572

关键词：atp9基因；RNA编辑；细胞质雄性不育；樱香A；樱香B；

Keywords:atp9, Cytoplasmicmalesterile(CMS), RNAediting, YingXiangA, YingXiangB,

摘 要 ：紫稻(Oryza sativa L.)细胞质雄性不育系是本实验室新构建的新型细胞质雄性不育系。本研究使用PCR、RT-PCR等技术,得到了紫稻不育系(樱香A)及其保持系(樱香B)线粒体atp9基因的基因组序列和cDNA序列。通过对这些序列的分析发现:樱香A atp9 cDNA序列中,没有发生RNA编辑;而樱香Batp9 cDNA序列中有2个编辑位点,在樱香B cDNA序列2个编辑位点中,223位点由C替换为T,导致原来编码精氨酸密码子成为终止密码子,保证atp9 mRNA编码一个"正常长度"的ATP9多肽。而由于没有终止密码子,樱香A mRNA就不能翻译成正常的多肽。上述研究表明,RNA编辑在生成正常的ATP9多肽的过程中发挥了重要作用,同时也说明RNA编辑可能与细胞质雄性不育相关。

Abstract:On the base of construction of a new type of cytoplasmic male sterile line Zidao A,we analyzed the editing of transcripts of mitochondrial ATP synthase subunit 9 gene(atp9)from CMS line and its maintainer line.With PCR,RT-PCR,and direct sequencing,complete nucleotide sequences were determined for the mitochondrial atp9 gene and its cDNA from two lines of Purple Rice Type rice(Oryza sativa L.):cytoplasmic male sterile line Ying Xiang A and its maintainer line Ying Xiang B.The atp9 transcript of Ying Xiang A was shown to have no editing sites and the transcript of Ying Xiang B was shown to have 2 editing sites with changes affecting the amino acid sequence of the protein product.The editing of the atp9 transcript from Ying Xiang B was found to change an arginine codon into a termination codon,shortening the protein of Ying Xiang B to the"standard"size.The Ying Xiang A transcript,which has no termination codon,cannot be translated to a normal protein.The results demonstrate the important role of RNA editing in the production of the functional ATP9 subunit and suggest that RNA editing could be likely associated with cytoplasmic male sterility.

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