PDF(Pubmed)
Abstract：
During the evolution of the RNA, short RNAs are thought to have joined together to form long RNAs, enhancing their function as ribozymes. Previously, the artificial R3C ligase ribozyme (73 nucleotides) was successfully reduced to 46 nucleotides; however, its activity decreased significantly. Therefore, we aimed to develop allosteric ribozymes, whose activities could be regulated by effector compounds, based on the reduced R3C ligase ribozyme (R3C-A). Among the variants prepared by fusing an ATP-binding aptamer RNA with R3C-A, one mutant showed increased ligation activity in an ATP-dependent manner. Melting temperature measurements of the two RNA mutants suggested that the region around the aptamer site was stabilized by the addition of ATP. This resulted in a suitable conformation for the reaction at the ligation site. Another ribozyme was prepared by fusing R3C-A with a l-histidine-binding aptamer RNA, and the ligase activity increased with increasing l-histidine concentrations. Both ATP and l-histidine play prominent roles in current molecular biology and the interaction of RNAs and these molecules could be a key step in the evolution of the world of RNAs. Our results suggest promise in the development of general allosteric ribozymes that are independent of the type of effector molecule and provide important clues to the evolution of the RNA world.
摘要：
在RNA的进化过程中，短RNA被认为已经连接在一起形成长RNA，增强它们作为核酶的功能。以前,人工R3C连接酶核酶(73个核苷酸)成功地减少到46个核苷酸;然而,其活性显著下降。因此,我们的目标是开发变构核酶，其活性可以由效应化合物调节，基于还原的R3C连接酶核酶(R3C-A)。在通过将ATP结合适体RNA与R3C-A融合制备的变体中，一个突变体以ATP依赖性方式显示出增加的连接活性。两种RNA突变体的解链温度测量表明,通过添加ATP来稳定适体位点周围的区域。这导致在连接位点处反应的合适构象。通过将R3C-A与1-组氨酸结合适体RNA融合制备另一种核酶，连接酶活性随着l-组氨酸浓度的增加而增加。ATP和1-组氨酸在当前的分子生物学和RNA的相互作用中起着重要作用,并且这些分子可能是RNA世界进化的关键步骤。我们的结果表明，与效应分子的类型无关的一般变构核酶的开发有望，并为RNA世界的进化提供了重要线索。
