TIME RESOLVED SYNCHROTRON XRAY FOOTPRINTING OF NUCLEIC ACIDS

核酸的时间分辨同步加速器 X 射线足迹

• 批准号: 6345072
• 负责人: MARK R CHANCE
• 金额: $ 4.66万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-01 至 2001-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6345072
• 关键词: biological products; biomedical equipment development; biomedical resource; biotechnology; enzymes; nucleic acids; proteins; radiology; spectrometry; synchrotrons; technology /technique

Hydroxyl radicals (*OH) can cleave the phosphodiester backbone of nucleic acids and are valuable reagents in the study of nucleic acid structure and protein-nucleic acid interactions through "footprinting" studies. Irradiation of solutions by high flux "white light" x-ray beams based on bending magnet beamlines at the National Synchrotron Light Source (NSLS) yields sufficient concentrations of *OH so that quantitative nuclease protection ("foot-printing") studies of DNA and RNA can be conducted with 10 - 20 msec x-ray exposure. The utility of this timescale for nucleic acid cleavage is demonstrated by synchrotron x-ray time-resolved "footprinting" analyses of the Mg2+ -dependent folding of the Tetrahymena thermo-philia L-21 Sca I ribozyme RNA. Since RNA folding progress curves over timescales from msec to minutes have been obtained for 25 regions of the ribozyme, this research provides an unprecedented structural kinetic picture of the folding of a large macromolecule. Synchro-tron x-ray "footprinting" is a new approach of general applicability for the study of time-re-solved structural changes of nucleic acid conformation and protein-nucleic acid complexes.

羟基自由基 (*OH) 可以裂解磷酸二酯主链 核酸，是核酸研究中有价值的试剂 通过“足迹”了解结构和蛋白质-核酸相互作用 研究。 高通量“白光”X 射线照射溶液 基于国家同步加速器弯曲磁体束线的光束 光源 (NSLS) 产生足够浓度的 *OH，以便 DNA 的定量核酸酶保护（“足迹”）研究 RNA 可以在 10 - 20 毫秒的 X 射线照射下进行。 的效用 核酸裂解的时间尺度由 Mg2+ 的同步加速器 X 射线时间分辨“足迹”分析 嗜热四膜虫 L-21 Sca I 的依赖性折叠 核酶RNA。 由于 RNA 折叠进度曲线随时间尺度变化 核酶的 25 个区域已获得毫秒到分钟的时间， 这项研究提供了前所未有的结构动力学图景 大分子的折叠。 同步加速器X射线 “足迹法”是一种普遍适用的新方法 核酸时间分辨结构变化的研究 构象和蛋白质-核酸复合物。