带有bZIP DNA-结合区域的GCN4蛋白质和它的模型系统

GCN4 protein with bZIP DNA-binding motif and its model systems

GCN4是转录调节蛋白质二聚体,它可以在氨基酸饥饿的条件下控制酵母中histidine的生物合成。GCN4DNA结合区域是碱性区域/leucine拉链（bZIP）结构。GCN4的leucine拉链结构二聚成coiled-coil结构。GCN4的碱性区域结构光滑地插入AP-1DNA片段的两边并与DNA主沟的对面结合。脚印跟踪（foot-printing）和one/two hybrid system protocols被用来研究GCN4和AP-1结合的定量构效关系。Max2-Jun是来自GCN4的变体之一。Max2-Jun的检测和表达的初步结果（Agro gel和HPLC）以及Max2-Jun和Ebox/XRE1的初步结合实验（foot-printing）表明Max2-Jun可能伴随一些不需要的组分。这些不需要的组分可能不能从需要的DNA片段/蛋白质中除去并且可能影响（正的/负的）需要的结合作用。进一步的GCN4蛋白质模型系统的设计正在进行中。

GCN 4 is a dimeric transcriptional regulatory protein that controls histidine biosynthesis in yeast under the conditions of amino acid starvation.GCN 4DNA-binding domain is a basic region/leucine zipper(bZIP)structure.The leucine zipper structure of GCN 4 dimerizes into the coiled-coil structre.The basic region structure of GCN 4smoothly forks to either side of the AP-1DNA piece and bind opposite sides of the DNA major groove.Foot-printing and one/two hybrid system protocols are used to study the qualitative structure-activity relationship of the binding between GCN 4and AP-1.Max2-Jun is one of the variants derived from GCN 4.Preliminary results(Agro gel and HPLC)of the detection and expression of Max 2-Jun and the preliminary binding experiments(foot-printing)between Max2-Jun and Ebox/XRE1indicated that Max 2-Jun may be accompanied by some unexpected components.These unexpected components may not be removed from the expected DNA piece/protein and may(positively/negatively)affect the expected binding interaction.The further design of the model protein of GCN4is in progress.