在张力下单个DNA分子的紧缩动态
Wen-Bo Fu1, Xiao-Ling Wang, Xing-Hua Zhang
1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China.
Journal of the American Chemical Society
|November 23, 2006
概括
六氨基化物诱导不连续的DNA紧缩和解在特定的力量下. DNA 折叠和展开涉及由紧缩动力学影响的元稳定状态之间的过渡.
科学领域:
- 生物物理学的生物物理.
- 分子生物学分子生物学
- 材料科学 材料科学 材料科学
背景情况:
- 对于细胞内的基因组组织来说,DNA紧缩至关重要.
- 了解强力下的DNA结构转变是分子力学的关键.
研究的目的:
- 为了研究由六胺化诱导的DNA紧缩的动态.
- 分析DNA巨型体的依赖力结构转变.
主要方法:
- 使用横向的磁子来对DNA施加恒定的力.
- 在不同力 (0.51.7 pN和>6 pN) 下研究了DNA紧缩和解动力学.
主要成果:
- 观察到不连续的DNA紧缩事件 (大约. 每次事件的270纳米DNA) 在0.51.7 pN之间.
- 发现力量>6pN诱导间歇性,逐步解开DNA巨.
- 识别了折叠/展开作为变态稳定状态与电压依赖的能量屏障之间的过渡.
结论:
- DNA紧缩和解是复杂的过程,涉及不同的结构状态.
- 压缩动力学和取决于力量的能量障碍决定了 DNA 在 toroid 中的排序程度.
相关概念视频
DNA Packaging
Overview
The Nucleosome
DNA in a human cell is almost 2m long and it is packed inside a tiny nucleus that is only a few microns in diameter. The level of compaction of DNA inside the nucleus is astonishing. It is organized into several sequentially higher levels of compaction to fit into such a tiny space. The most compact form of DNA is a chromosome that can be seen under a microscope in a dividing cell.
DNA is wound twice around a protein complex called histone core, that consist of 8 histone proteins. This complex...
DNA is wound twice around a protein complex called histone core, that consist of 8 histone proteins. This complex...
Chromatin Packaging
Each human somatic cell contains 6 billion base-pairs of DNA. Each base-pair is 0.34 nm long, which means that each diploid cell contains a staggering 2 meters of DNA. How is such a long DNA strand packed inside a nucleus measuring only 10 - 20 microns in diameter?
The chromatin
In combination with specialized DNA binding protein called Histones, the DNA double helix forms a compact DNA: protein complex called chromatin. The chromatin itself is further compacted into higher-order structures.
The chromatin
In combination with specialized DNA binding protein called Histones, the DNA double helix forms a compact DNA: protein complex called chromatin. The chromatin itself is further compacted into higher-order structures.
The Nucleosome
Human DNA is almost two meters long. However, it is compressed inside a tiny nucleus measuring only a few microns in diameter. To make this degree of compaction possible, DNA is organized into several sequential levels so that it can fit into such a tiny space. The most compact form of DNA is a chromosome that can be seen under a microscope in a dividing cell.
In a chromosome, DNA is wound twice around a protein complex called a histone octamer core, which consists of 8 histone proteins. This...
In a chromosome, DNA is wound twice around a protein complex called a histone octamer core, which consists of 8 histone proteins. This...
Chromatin Packaging
Each human somatic cell contains 6 billion base pairs of DNA. Each base pair is 0.34 nm long, meaning each diploid cell contains a staggering 2 meters of DNA. This long DNA strand is packed inside a nucleus measuring only 10-20 microns in diameter with the help of specialized DNA-binding proteins called histones. Together they form a compact DNA-protein complex called chromatin. The chromatin is further compacted into higher-order structures. The highest level of compaction is achieved during...
DNA Bacteriophages
Bacteriophages, or phages, are viruses that specifically infect bacteria, utilizing their genetic material to hijack host cellular machinery for replication. DNA bacteriophages employ single-stranded DNA (ssDNA) or double-stranded DNA (dsDNA) genomes. These phages exhibit diverse replication strategies and host interactions, influencing their ecological roles and applications in biotechnology and medicine.ssDNA BacteriophagesssDNA phages, with their small genomes, utilize unique strategies to...


