【摘要】 为研究１６ｂＰ ＰＵＲ ｂｏｘ中除第３位的Ｇ与第１４位的Ｃ外，余下６个完全保守碱基的４个在与ＰｕｒＲ阻遏蛋白结合中的功能，对它们分别做了定点突变，使其分别从Ｃ、Ａ、Ａ和Ｔ突变为Ｇ、Ｇ、Ｇ和Ｃ。凝胶阻滞实验结果表明，含上述指定突变的ＰＵＲ ｂｏｘ均不能与ＰｕｒＲ阻遏蛋白结合。由此证明，这４个保守碱基对维持ＰＵＲ ｂｏｘ的功能是必须的，其中任一改变都导致ＰＵＲ ｂｏｘ功能的丧失。更多还原

【Abstract】 To study binding funtion of 4 consensus bases in 16bp PUR box with purR protein, the directed site mutation for each was carried out which mutate from C to G, A to G, A to G, T to C, respectively. Gel retardation showed that the PUR box carrying a reserved mutation could not bind with purR protein. It suggested that all these consensus base pairs are necessary to hold the normal binding function of PUR box with purR protein.更多还原