Branlant C, Krol A, Lazar E, Haendler B, Jacob M, Galego-Dias L, Pousada C
Nucleic Acids Res. 1983 Dec 10;11(23):8359-67. doi: 10.1093/nar/11.23.8359.
The nucleotide sequence of chicken, pheasant, duck and Tetrahymena pyriformis U5 RNAs as well as that of new mammalian variant U5 RNAs was determined and compared to that of rat and HeLa cells U5 RNAs. Primary structure conservation is about 95% between rat and human cells, 82% between mammals and birds and 57% between the Protozoan and mammals. The same model of secondary structure, a free single-stranded region flanked by two hairpins can be constructed from all RNAs and is identical to the model previously proposed for mammalian U5 RNA on an experimental basis (1). Thus, this model is confirmed and is likely to be that of an ancestor U5 RNA. The 3' region of the U5 RNA molecule constitutes domain A, and is common to U1, U2, U4 and U5 RNAs (2). The characteristic nucleotide sequences of domain A are highly conserved throughout the phylogenetic evolution of U5 RNA suggesting that they are important elements in the function of the four small RNAs. Another region of high evolutionary conservation is the top part of the 5' side hairpin whose conserved sequence is specific to U5 RNA. It might participate in the particular function of U5 RNA.
测定了鸡、雉、鸭和梨形四膜虫U5 RNA以及新的哺乳动物变体U5 RNA的核苷酸序列，并与大鼠和HeLa细胞的U5 RNA序列进行了比较。大鼠和人类细胞之间的一级结构保守性约为95%，哺乳动物和鸟类之间为82%，原生动物和哺乳动物之间为57%。所有RNA均可构建相同的二级结构模型，即由两个发夹环绕的游离单链区，该模型与之前基于实验提出的哺乳动物U5 RNA模型相同(1)。因此，该模型得到了证实，并且可能是祖先U5 RNA的模型。U5 RNA分子的3'区域构成结构域A，是U1、U2、U4和U5 RNA共有的(2)。结构域A的特征性核苷酸序列在U5 RNA的整个系统发育进化过程中高度保守，表明它们是这四种小RNA功能中的重要元件。另一个高度进化保守区域是5'侧发夹的顶部，其保守序列是U5 RNA特有的。它可能参与U5 RNA的特殊功能。
