Romero D P, Blackburn E H
Department of Microbiology and Immunology, University of California, San Francisco 94143.
Cell. 1991 Oct 18;67(2):343-53. doi: 10.1016/0092-8674(91)90186-3.
The RNA moiety of the ribonucleoprotein enzyme telomerase contains the template for telomeric DNA synthesis. We present a secondary structure model for telomerase RNA, derived by a phylogenetic comparative analysis of telomerase RNAs from seven tetrahymenine ciliates. The telomerase RNA genes from Tetrahymena malaccensis, T. pyriformis, T. hyperangularis, T. pigmentosa, T. hegewishii, and Glaucoma chattoni were cloned, sequenced, and compared with the previously cloned RNA gene from T. thermophila and with each other. To define secondary structures of these RNAs, homologous complementary sequences were identified by the occurrence of covariation among putative base pairs. Although their primary sequences have diverged rapidly overall, a strikingly conserved secondary structure was identified for all these telomerase RNAs. Short regions of nucleotide conservation include a block of 22 totally conserved nucleotides that contains the telomeric templating region.
核糖核蛋白酶端粒酶的RNA部分包含端粒DNA合成的模板。我们提出了一种端粒酶RNA的二级结构模型，该模型是通过对七种四膜虫纤毛虫的端粒酶RNA进行系统发育比较分析得出的。克隆了来自马六甲四膜虫、梨形四膜虫、高角四膜虫、色素四膜虫、赫格维希四膜虫和查顿青光眼的端粒酶RNA基因，进行了测序，并与先前克隆的嗜热四膜虫RNA基因以及它们彼此进行了比较。为了确定这些RNA的二级结构，通过推定碱基对之间的共变现象鉴定了同源互补序列。尽管它们的一级序列总体上迅速分化，但所有这些端粒酶RNA都鉴定出了惊人保守的二级结构。核苷酸保守的短区域包括一个由22个完全保守的核苷酸组成的区域，该区域包含端粒模板区域。
