蓝藻非编码RNA Yfr7的生物学特征分析

Biological Characteristic Analysis of Non-Coding RNA Yfr7 in Cyanobacteria

Yfr家族是广泛存在于蓝藻基因组中的一类非编码RNA,在细胞代谢和环境适应方面发挥重要作用。文中选取Yfr7作为研究对象,首先根据序列特征确定Yfr7的二级结构,然后结合动态规划和自由能的计算方法预测Yfr7的调控基因,从细胞定位、分子功能和调控路径三方面对这些基因进行分析,以快速发现Yfr7的功能,最后通过构建进化树来揭示Yfr7的遗传特征。结果表明:Yfr7拥有独立的启动子区和操纵子,通过保守片段5'-GTGCTCTGATCTGACT-3'与目标mRNA序列互补来调控特定基因的表达;目标基因包括看家基因和酶基因,这些目标基因的功能说明Yfr7广泛参与细胞的次级代谢;进化树聚类表明Yfr7与菌株光照类型有关,参与蓝藻最重要的光合反应;Yfr7与6S RNA在序列、结构和遗传距离上都高度一致,推测可能来自同一个祖先。这些研究结果可为进一步开展相关实验研究提供理论基础。

Yfr family is a kind of non-coding RNA that widely distributes in genomes of cyanobacteria and plays an important role in cellular metabolism and environment adaption. In this study, the authors selected Yfr7 as a template and determined its secondary structure according to the sequence characteristics firstly. Then, they predicted the target genes of Yfr7 based on dynamic programming and free energy, and analyzed these target genes in cellular localization, molecular function and regulatory pathway in order to discover the function of Yfr7. At last, they constructed the phylogenetic tree to understand its genetic trait. The results show that Yfr7 has an independent promoter and operon. Regulation is performed by sequence complementation between the conservative sequence 5＇-GTGCTCTGATCTGACT-3＇ of Yfr7 and mRNA of the target genes. The target genes of Yfr7 include housekeeping genes and enzyme coding genes, whose functions reveal that Yfr7 is involved in extensive secondary metabolism in cyanobacteda. The clusters based on phylogenetic tree show that Yfr7 is associated with light absorption and participates in the photosynthesis. Besides, Yfr7 is highly consistent with 6S RNA in sequence, structure and evolution, indicating that they are likely from the same ancestor. Our findings provide theoretical basis for further experiment study.