相关实验视频
Updated: Jul 19, 2026

12:13
Single-Molecule Imaging of Nuclear Transport
Published on: June 9, 2010
在双重DNA寡核酸中激素阴离子运输的机制
Chu-Sheng Liu1, Rigoberto Hernandez, Gary B Schuster
1School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, USA.
Journal of the American Chemical Society
|March 5, 2004
概括
在DNA寡合体中,光诱导的电子转移揭示了激素离子在微秒时间尺度上的位置之间跳跃. 这种跳跃受到DNA序列的影响,并由语音辅助的极子机制解释.
科学领域:
- 生物物理学的生物物理.
- DNA 化学 基因化学
- 摄影化学的使用.
背景情况:
- 转基因改造的DNA寡合体能够研究光诱导的电子转移.
- DNA的结构影响了基离子的迁移,这可能导致链分裂.
研究的目的:
- 为了研究光诱导的单电子氧化和DNA寡合体中的基质离子迁移.
- 为了确定DNA中激素离子跳跃和捕获的动力学.
- 阐明DNA中激素阳离子转运的机制.
主要方法:
- 合成具有共价连接的 antraquinone (AQ) 和不同 (A) 或 (T) 分段的 DNA 寡合体.
- 对AQ-DNA合体进行紫外线照射,以启动电子转移.
- 在 piperidine 处理后,DNA 链裂变的分析.
- 动力模型的数值解法,以提取速率常数.
主要成果:
- 光诱导的电子转移将基离子注入DNA中,该基离子迁移并导致GG部位的链裂变.
- 确定了两个速率常量:k ((hop) 对于激素离子跳跃和k ((trap) 对于不可逆转的反应.
- 激素离子跳跃发生在微秒时间尺度上,并且取决于 (A) (n) 和 (T) (n) 段的长度.
结论:
- 在双重DNA中,激素离子跳跃是一个微秒的过程.
- 跳跃率 (k(hop)) 系统地受到DNA序列的影响.
- 这种机制与热激活的可声波辅助波拉龙跳跃相一致.
相关概念视频
Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
Nuclear Protein Sorting
Nuclear protein sorting is the selective trafficking of histones, polymerases, gene regulatory proteins into the nucleus and exporting RNAs and ribosomes to the cytosol. It is a tightly controlled process that regulates gene expression within a cell.
Proteins targeted to the nucleus carry nuclear localization signals or NLS recognized by import receptors in the cytosol. Similarly, proteins with nuclear export signals are recognized by export receptors. Import and export receptors are...
Proteins targeted to the nucleus carry nuclear localization signals or NLS recognized by import receptors in the cytosol. Similarly, proteins with nuclear export signals are recognized by export receptors. Import and export receptors are...
Nuclear Export
The nucleus restricts several proteins within and allows others to pass. The restricted proteins possess a nuclear retention sequence or NRS, anchoring them to the nuclear lamins and preventing their transport to the cytosol. The non-restricted proteins, after their synthesis, are transported to their site of action, such as the cytosol or other organelles, with the help of nuclear export signals or NES.
NES are of three types- the canonical 10-residue long leucine-rich signal and other...
NES are of three types- the canonical 10-residue long leucine-rich signal and other...
Directionality of Nuclear Transport
Ras-related nuclear protein or Ran is a small G protein that cycles between its GTP and GDP bound states. Ran specific regulators, a Ran GTPase Activating Protein or RanGAP present in the cytosol and a Ran guanine nucleotide exchange factor or RanGEF present inside the nucleus regulate GTP/GDP exchange. A high concentration of GTP inside the cells, in addition to this asymmetric distribution of Ran-specific regulators, leads to a higher RanGTP concentration inside the nucleus. This...
Regulation of Nuclear Protein Sorting
Nuclear protein sorting regulates nucleus composition and gene expression, crucial for determining the fate of a eukaryotic cell. Hence, the entry and exit of molecules across the nuclear envelope is a tightly controlled process. Nuclear protein sorting can be inhibited by one of the following ways: 1) masking cargo signal sequences, 2) modifying the nuclear receptor's affinity for cargo, 3) controlling the nuclear pore size, 4) retaining the cargo during its transit to the cytosol or the...
Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...

