CAP-DNA复合体的晶体结构:DNA被曲了90度
S C Schultz1, G C Shields, T A Steitz
1Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511.
概括
晶体结构显示,大肠杆菌的催化剂基因激活蛋白 (CAP) 通过特定的基对曲线将DNA曲90度. 这种DNA曲和蛋白质-DNA相互作用是转录激活的关键.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 遗传学 是一个遗传学.
背景情况:
- 催化剂基因激活蛋白 (CAP) 是大肠杆菌中的一个关键的转录因子.
- 了解CAP-DNA相互作用对于破译基因调节机制至关重要.
研究的目的:
- 阐明大肠杆菌催化剂基因激活蛋白 (CAP) 通过DNA结合和曲的结构基础.
- 研究DNA序列和蛋白质-DNA相互作用在转录激活中的作用.
主要方法:
- 使用X射线晶体学来确定CAP-DNA复合体的3安格斯特罗姆分辨率结构.
- 对蛋白质-DNA接口和DNA螺旋参数的分析.
主要成果:
- 晶体结构显示,在CAP复合体内,DNA被曲了90度.
- 在TG/CA基对中观察到两个显著的扭曲,每个40度,导致DNA曲.
- CAP对特定序列的DNA识别涉及螺旋扭曲和直接与基对边缘的键.
结论:
- 该研究提供了关于CAP如何识别和扭曲DNA的原子层次见解.
- 观察到的DNA曲和特定相互作用解释了CAP在促进转录激活中的作用.
相关概念视频
The DNA Helix
Overview
The DNA Helix
Overview
DNA as a Genetic Template
Two structural features of the DNA molecule provide a basis for the mechanisms of heredity: the four nucleotide bases and its double-stranded nature. The Watson-Crick model of double-helical DNA structure, proposed in 1952, drew heavily upon the X-ray crystallography work of researchers Rosalind Franklin and Maurice Wilkins. Watson, Crick, and Wilkins jointly received the Nobel Prize in Physiology or Medicine for their work in 1962. Franklin was, controversially, excluded from the prize for...
DNA Helicases
DNA unwinding helicase enzymes are a type of motor protein. Motor proteins can translocate along filaments or polymers using energy generated from ATP hydrolysis. Helicases are involved in all the important cellular processes where DNA unwinding is required, such as DNA replication, repair, recombination, and transcription. They are present in all living organisms, but vary in their structure, function, and mechanism of action. For example, in prokaryotes, DnaB helicase binds and translocates...
The DNA Helix
Deoxyribonucleic acid, or DNA, is the genetic material responsible for passing traits from generation to generation in all organisms and most viruses. DNA is composed of two strands of nucleotides that wind around each other to form a spring-like structure called a double helix. However, the double helix is not perfectly symmetrical. Instead, there are regularly occurring grooves in the structure. The major groove occurs where the sugar-phosphate backbones are relatively far apart. This space...
Nucleic Acid Structure
The pentose sugar in DNA is deoxyribose, while in RNA the pentose sugar is ribose. The difference between the sugars is the presence of the hydroxyl group on the ribose's second carbon and a hydrogen on the deoxyribose's second carbon. The phosphate residue attaches to the hydroxyl group of the 5′ carbon of one sugar and the hydroxyl group of the 3′ carbon of the sugar of the next nucleotide, which forms a 5′ to 3′ phosphodiester linkage.
DNA Structure
DNA has a double-helix structure. The...
DNA Structure
DNA has a double-helix structure. The...


