针对点突变癌基因T24－ras转录物的核酶性质研究

Study on the Properties of Ribozyme Targeted to the Transcripts of Site-Mutant Oncogene T24-ras

通过改变核酶体外反应的各种条件，对针对点突变癌基因Ｔ２４－ｒａｓ转录物的核酶Ｒ８的性质进行了系统研究，结果表明：Ｒ８切割底物反应的最适ｐＨ值约为８．２，最适温度为５０℃，反应必须有镁离子参加，生理环境中常见的阴离子对反应没有影响，一些变性剂能够促进反应的进行，Ｒ８切割底物的反应为二级反应。

The properties of the ribozyme R8,which is targeted to the 12th codon G-T mutant oncogene T24-ras,was systematically studied by changing the reactive conditions in vitro.It has been determined that the optimal pH for cleavage reaction of R8 is about 8.2,the optimal temperature is 50℃.Mg2+ is necessary to the cleavage reaction,some negative ions ordinarily occurred in physiological environment do not affect the cleavage reaction,and some denaturational agents increase the cleavage efficiency.It has also been figured out that the cleavage reaction of RS is a second order reaction.