RNA编辑修复藻苔(Takakia lepidozioides)叶绿体accD基因中的突变

RNA Editing Restores Mutations in the Chloroplast Gene accD of Takakia lepidozioides

藻苔(Takakia lepidozioides)叶绿体基因组中存在着非常高的RNA编辑频率,这种现象至今没有得到很好的解释。本研究采用比较基因组学方法,对小立碗藓(Physcomitrella patens)、青苔(Syntrichia ruralis)和藻苔3种苔藓植物中accD基因的DNA序列和基因编码的蛋白氨基酸序列进行比较分析。研究发现,经过RNA编辑,藻苔的基因产物获得了与其同源基因相同的氨基酸序列。藻苔中高频发生的RNA编辑是对基因组中DNA突变的一种修复,提高了藻苔对强辐射环境的生存适应能力。

RNA editing highly occurs in Takakia lepidozioides chloroplast. The reason underlying the phenominon remains unclear. In this study, with comparative genomic approach, we analized the sequences of the gene accD and its protein products in mosses PhyscomitreUa patens, Syntrichia ruralis, and Takakia lepidozioides. We find that RNA editing restores mutations in the gene accD of T. lepidozioides, T. lepidozioides aquires the same amino acid sequence as its homologs in Physcomitrella patens and Syntrichia ruralis. The high occurrence of RNA editing in T. lepidozioides chloroplast is an important stratigy to restore DNA mutations. RNA editing enhences T. lepidozioides the adaptation to survive under the high radiation enviroment.