Brown J W, Haas E S, James B D, Hunt D A, Liu J S, Pace N R
Department of Biology, Indiana University, Bloomington 47405.
J Bacteriol. 1991 Jun;173(12):3855-63. doi: 10.1128/jb.173.12.3855-3863.1991.
The secondary structures of the eubacterial RNase P RNAs are being elucidated by a phylogenetic comparative approach. Sequences of genes encoding RNase P RNA from each of the recognized subgroups (alpha, beta, gamma, and delta) of the proteobacteria have now been determined. These sequences allow the refinement, to nearly the base pair level, of the phylogenetic model for RNase P RNA secondary structure. Evolutionary change among the RNase P RNAs was found to occur primarily in four discrete structural domains that are peripheral to a highly conserved core structure. The new sequences were used to examine critically the proposed similarity (C. Guerrier-Takada, N. Lumelsky, and S. Altman, Science 246:1578-1584, 1989) between a portion of RNase P RNA and the "exit site" of the 23S rRNA of Escherichia coli. Phylogenetic comparisons indicate that these sequences are not homologous and that any similarity in the structures is, at best, tenuous.
通过系统发育比较方法，正在阐明真细菌核糖核酸酶P RNA的二级结构。现已确定了来自变形菌纲各公认亚组（α、β、γ和δ）的编码核糖核酸酶P RNA的基因序列。这些序列使得核糖核酸酶P RNA二级结构的系统发育模型能够精确到几乎碱基对水平。人们发现，核糖核酸酶P RNA之间的进化变化主要发生在高度保守的核心结构外围的四个离散结构域中。利用这些新序列对核糖核酸酶P RNA的一部分与大肠杆菌23S rRNA的“出口位点”之间所提出的相似性（C. 格里耶 - 高田、N. 卢梅尔斯基和S. 阿尔特曼，《科学》246:1578 - 1584，1989年）进行了严格检验。系统发育比较表明，这些序列并非同源，而且结构上的任何相似性充其量也是微弱的。
