蛋白质-DNA复合体的Allosteric抑制通过聚胺-插曲器结合物
Eric J Fechter1, Peter B Dervan
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|July 10, 2003
概括
新的头聚胺-氨酸结合物通过阻断蛋白质-DNA相互作用来抑制基因转录. 这些分子特别结合DNA,改变其结构以防止转录因子结合.
科学领域:
- 分子生物学分子生物学
- 化学生物学 化学生物学
- 遗传学 是一个遗传学.
背景情况:
- 蛋白质-DNA相互作用的特定序列抑制是化学调节基因表达的关键.
- 针头聚胺可以抑制蛋白质-DNA复合体,但它们的有效性各不相同.
- 聚胺和像bZip因子这样的大槽结合蛋白可以占据相同的DNA小槽.
研究的目的:
- 为了合成和描述新型的头针聚胺-阿克里丁结合物.
- 为了研究这些结合物的DNA结合亲和力和序列特异性.
- 为了确定这些合物是否可以抑制蛋白质-DNA结合,特别是由GCN4 bZip蛋白.
主要方法:
- 合成了四种发针聚胺-氨酸合物.
- 用DNA结合测试来确定亲和力和序列特异性.
- 测量DNA解,以评估阿克里丁干.
- 使用GCN4 bZip蛋白及其向DNA序列进行抑制测定.
主要成果:
- 合成的聚胺 - 氨酸合物与DNA小沟结合,具有高度亲和力和序列特异性.
- 这些结合物诱导DNA解 (14-15度),表明了阿克里丁间.
- 结合物有效地通过GCN4 bZip蛋白抑制大沟DNA结合.
结论:
- 聚胺-氨酸合物结合了特定序列的小沟结合和局部DNA解.
- 这种双重机制在DNA中产生了全性结构变化.
- 这一类分子显示出作为转录因子结合的一般抑制剂的潜力,无论蛋白质-DNA结构如何.
相关概念视频
Allosteric Regulation
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Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...
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Certain biochemical processes, such as embryonic development and cell growth regulation, depend on the repression of specific genes. DNA binding proteins known as eukaryotic transcription inhibitors regulate the repression of gene expression in eukaryotes. The presence of these inhibitors at the required location and time in the cell is triggered by the presence of hormones and additional signals from other cells.
Eukaryotic transcription inhibitors usually contain two distinct domains, a DNA...
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Binding sites linkages can regulate a protein's function. For example, enzyme activity is often regulated through a feedback mechanism where the end product of the biochemical process serves as an inhibitor.
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis pathway,...
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis pathway,...


