Emilsson Gail Mitchell, Nakamura Shingo, Roth Adam, Breaker Ronald R
Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06520-8103, USA.
RNA. 2003 Aug;9(8):907-18. doi: 10.1261/rna.5680603.
The speed at which RNA molecules decompose is a critical determinant of many biological processes, including those directly involved in the storage and expression of genetic information. One mechanism for RNA cleavage involves internal phosphoester transfer, wherein the 2'-oxygen atom carries out an SN2-like nucleophilic attack on the adjacent phosphorus center (transesterification). In this article, we discuss fundamental principles of RNA transesterification and define a conceptual framework that can be used to assess the catalytic power of enzymes that cleave RNA. We deduce that certain ribozymes and deoxyribozymes, like their protein enzyme counterparts, can bring about enormous rate enhancements.
RNA分子分解的速度是许多生物过程的关键决定因素，包括那些直接参与遗传信息存储和表达的过程。RNA切割的一种机制涉及内部磷酸酯转移，其中2'-氧原子对相邻的磷中心进行类似SN2的亲核攻击（酯交换反应）。在本文中，我们讨论了RNA酯交换反应的基本原理，并定义了一个概念框架，可用于评估切割RNA的酶的催化能力。我们推断，某些核酶和脱氧核酶，与它们的蛋白质酶对应物一样，可以带来巨大的速率提升。
