THE CRYSTAL-STRUCTURE OF AN ALL-RNA HAMMERHEAD RIBOZYME - A PROPOSED MECHANISM FOR RNA CATALYTIC CLEAVAGE
THE CRYSTAL-STRUCTURE OF AN ALL-RNA HAMMERHEAD RIBOZYME - A PROPOSED MECHANISM FOR RNA CATALYTIC CLEAVAGE
复制标题
DOI：
10.1016/s0092-8674(05)80004-2
复制
发表时间：
1995-06-30
期刊：
影响因子：
64.5
通讯作者：
KLUG, A
中科院分区：
文献类型：
--
作者：
SCOTT, WG;FINCH, JT;KLUG, A
我们已经解析了全 RNA 锤头核酶的晶体结构，该核酶在活性位点掺入了单个 2'-O-甲基胞嘧啶以防止裂解。所使用的条件与最近的另一个解决方案有四个显着的不同：首先，它是一种全 RNA 核酶，而不是 DNA-RNA 杂合体；其次，核酶主链的连接性不同；第三，晶体是在盐浓度低得多的情况下生长的；第四，晶体封装方案有很大不同。尽管如此，全RNA锤头核酶的三维结构与之前的结构相似。鉴定出五个潜在的 Mg(II) 结合位点，其中一个位于核酶催化袋附近。在此基础上，以及与tRNA（Phe）结构同源尿苷转角中的金属结合位点进行比较，我们提出了RNA催化裂解的机制。
We have solved the crystal structure of an all-RNA hammerhead ribozyme having a single 2'-O-methyl cytosine incorporated at the active site to prevent cleavage. The conditions used differ from those in another recent solution in four significant ways: first, it is an all-RNA ribozyme rather than a DNA-RNA hybrid; second, the connectivity of the ribozyme backbone strands is different; third, the crystals were grown in the presence of a much lower concentration of salt; and fourth, the crystal packing scheme is very different. Nevertheless, the three-dimensional structure of the all-RNA hammerhead ribozyme is similar to the previous structure. Five potential Mg(II)-binding sites are Identified, including one positioned near the ribozyme catalytic pocket. Upon this basis, as well as upon comparisons with the metal-binding sites in the structurally homologous uridine turn of tRNA(Phe), We propose a mechanism for RNA catalytic cleavage.