Detection of RNA editing and reconstruction of plant molecular phylogenetic tree

1、金鱼藻中的RNA编辑在台湾花角藻叶绿体中编辑了20多个基因的转录本。每1000个碱基的编辑位点数为20至4个，未观察到沉默编辑。发现胞苷（C）转化为尿苷（U）的位点与U转化为C的位点几乎相同。每个编辑位点由位于同一RNA中的向导RNA（gRNA）决定。在cox 1转录本的420个碱基区域内，观察到30个编辑位点。2、地钱中的RNA编辑在4种地钱线粒体cox 1转录本中未发现RNA编辑。3、石松中的RNA编辑在4种石松叶绿体atpB转录本中发现了大量的RNA编辑，其中包括U到C的转换。在相同的RNA中也发现了对应于gRNA的序列。在石松属植物线粒体中，cox 1转录本的420个核苷酸区域内发现了5个RNA编辑位点。蕨类植物中的RNA编辑在蕨类植物叶绿体中的14个基因的转录本中发现了约90个RNA编辑位点。除了C向U的转化外，还发现了U向C的转化。但在裸盖蕨叶绿体基因组的整个转录本中没有发现RNA编辑，因此RNA编辑的存在与绿色植物的进化没有严格的关系。基于叶绿体基因组核苷酸序列的系统发育关系即使在通过RNA编辑收集核苷酸序列时也没有改变。

1, RNA editing in hornwortsTranscripts from more than 20 genes were edited in the chloroplast of Anthoceros formosae. Number of editing sites were 20 to 4 per 1000 bases, and no silent editing was observed. The sites of cytidine (C) to uridine (U) conversion were found at almost the same amount as those of U to C conversion. Every editing site was determined by guide RNA (gRNA) which located in the same RNA.In the mitochondria of A. formosae, 30 editing sites were observed in 420 bases region of cox1 transcript. The conversion of U to C was also observed.2, RNA editing in liverwortsNo RNA editing was found in the mitochondrial cox1 transcript from 4 kinds of liverworts.3, RNA editing in lycopsidsExtensive RNA editing was found in atpB transcripts in the chloroplasts from 4 kinds of lycopsids, which included U to C conversion. Sequences corresponding to gRNA were also found in the same RNA. In the mitochondria from Lycopodium, 5 sites of RNA editing were found in the region of 420 nucleotides of cox1 transcript. They were C to U conversion.4, RNA editing in fernsAbout 90 sites of RNA editing were found in the transcripts of 14 genes in the chloroplasts from Pteridium. The conversion of U to C was also found in addition of C to U. However, no editing was expected through out the entire transcripts of chloroplast genome from Psilotum.In conclusion, existence of RNA editing was not strictly related with the evolution of green plant. Phylogenetic relationship based in the nucleotide sequence of chloroplast genome was not altered even when the nucleotide sequence was collected by RNA editing.