X-RAY DIFFRACTION--NUCLEIC ACID STRUCTURES

X 射线衍射--核酸结构

• 批准号: 3299866
• 负责人: ANDREW H WANG
• 金额: $ 15.72万
• 依托单位: UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-12-01 至 1994-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3299866
• 关键词: DNA; RNA; X ray crystallography; Z DNA; computer graphics /printing; conformation; nuclear magnetic resonance spectroscopy; nucleic acid hybridization; nucleic acid sequence; nucleic acid structure; oligonucleotides; synthetic nucleic acid; synthetic nucleotide

This proposal is designed to study the molecular basis of the conformational variabilities of nucleic acids, including DNA, RNA and DNA- RNA hybrid molecules by using single crystal x-ray diffraction technique as the major tool. It will be complemented by other spectroscopic studies, in particular high resolution nuclear magnetic resonance spectroscopy. Large amounts of pure DNA and RNA oligonucleotides with carefully chosen sequences will be synthesized on solid support resins either manually in solution, or by automated DNA synthesizer. Long RNA molecules will be prepared by T7 RNA polymerase system on DNA templates and they will be suitably purified for crystallization experiments. The following DNA and RNA molecular systems will be the major focus of this proposal. 1. Higher-ordered structures: triple-stranded, hairpins, cruciforms, pseudoknots, circular molecules, branched RNAs. 2. Sequence-dependent conformational analysis of double helical nucleic acids, including DNA, RNA, DNA-RNA hybrids. 3. Stable alternative nucleic acid conformations: Z-DNA, P-DNA, Hoogsteen Helix. 4. Nucleic acids with defects: Mismatch, bulge, missing base(apurine/apyrimidine), modified base (O6-mG/O4-mT), phosphotriester. The results from these structural studies both in solution and in solid states will be compared and they will be the basis for further theoretical analysis in order to fully understand the structure, dynamics and energetics of nucleic acids at the molecular level.

该提案旨在研究其分子基础 核酸的构象变异，包括DNA、RNA和DNA- RNA杂交分子通过使用单晶X射线衍射技术作为 主要工具。 它将得到其他光谱研究的补充， 特别是高分辨率核磁共振波谱。 大的 大量经过精心挑选的纯 DNA 和 RNA 寡核苷酸 序列将在固体支持树脂上手动合成 溶液，或通过自动 DNA 合成仪。 长RNA分子将 通过 T7 RNA 聚合酶系统在 DNA 模板上制备，它们将被 适当纯化用于结晶实验。 以下DNA和RNA分子系统将是本次会议的主要焦点 提议。 1. 高阶结构：三链、发夹、十字形、 假结、环状分子、分支RNA。 2. 双螺旋核酸的序列依赖性构象分析 酸，包括DNA、RNA、DNA-RNA杂交体。 3.稳定的替代核酸构象：Z-DNA、P-DNA、Hoogsteen 螺旋。 4. 有缺陷的核酸：错配、凸起、缺失 碱基（阿嘌呤/阿嘧啶）、修饰碱基（O6-mG/O4-mT）、磷酸三酯。 这些溶液和固体结构研究的结果 状态将被比较，它们将成为进一步理论的基础 分析以充分了解结构、动力学和 分子水平上的核酸能量学。