一个双价锤头型核酶在体外对两种不同植物病毒RNA的专一切割作用

根据锤头核酶模型，设计合成了一个以黄瓜花叶病毒（ＣＭＶ） 外壳蛋白（ＣＰ） 亚基因组ＲＮＡ 为底物的锤头型核酶（ＲＺＣ） 。在证明它能有效切割该底物后，再将这个核酶与一个能专一性切割烟草花叶病毒（ＴＭＶ） 移动蛋白（ ＭＰ） 亚基因组ＲＮＡ 的锤头型核酶（ＲＺ１） 相互串联构成了一个双价核酶（ＲＺ１Ｃ） 。体外结果表明，这个双价核酶能与相应的单价核酶ＲＺ１ 和ＲＺＣ 一样专一而有效地切割ＣＭＶＣＰ和ＴＭＶ ＭＰＲＮＡ。

Specific Cleavages of Two Different RNAs from TMV and CMV by a Di component Ribozyme in vitro

A hammerhead based ribozyme RZC was synthesized to cleave specifically a RNA fragment located in the coat protein (CP) gene region of cucumber mosaic virus (CMV) genome (Fig.1A). After its cleavage activity being confirmed (Fig.2, lane 5), RZC was further utilized to construct a di component ribozyme, RZ1C (Fig.1B) with a hammerhead ribozyme RZ1 specific to the movement protein (MP) gene region of tobacco mosaic virus (TMV) RNA genome. In vitro results indicated that RZ1C was able to cleave both CMV and TMV RNA sequences (Fig. 2, lanes 3,6) as efficiently and specifically as its mono ribozyme counterparts RZ1 and RZ1C.