Folding and Activity of the Hammerhead Ribozyme
Folding and Activity of the Hammerhead Ribozyme
复制标题
锤头核酶的折叠和活性
作者：
C. Hammann;D. Lilley
锤头状核酶是最小的溶核核酶，其在镁离子存在下通过酯交换反应进行主链切割。RNA通过与金属离子的结合在两个阶段中被诱导折叠成其活性构象。它们产生结构域2，即构建核酶的支架，以及结构域1，即核酶的活性中心。进一步的局部结构重排过程中的核酶的激活建议由一些晶体结构。105倍的速率增强可能是由折叠RNA结构环境中的金属离子参与和立体化学因素的组合引起的。
The hammerhead is the smallest of the nucleolytic ribozymes, that undergo backbone cleavage by a transesterification reaction in the presence of magnesium ions. The RNA is induced to fold into its active conformation by the binding of metal ions in two stages. These generate domain 2, the scaffold on which the ribozyme is built, and domain 1, the active centre of the ribozyme. Further local structural rearrangement during the activation of the ribozyme is suggested by a number of crystal structures. The 105‐fold rate enhancement is probably brought about by a combination of metal‐ion participation and stereochemical factors in the environment of the folded RNA structure.