LINKER HISTONE/DNA INTERACTIONS

连接子组蛋白/DNA 相互作用

• 批准号: 2187986
• 负责人: KENSAL E. VAN HOLDE
• 金额: $ 19.2万
• 依托单位: OREGON STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-08-01 至 1998-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2187986
• 关键词: DNA binding protein; chemical binding; chemical stability; chromatin; crosslink; genetic regulation; histones; molecular site; nonhistone nucleoprotein; nucleic acid sequence; nucleic acid structure; nucleosomes; polymerase chain reaction

Recent evidence from our laboratory indicates that the so-called "linker" histones (H1, H5, and their variants) can bind to certain DNA structures and sequences much more specifically than hitherto believed. In particular, these histones strongly bind to DNA crossover structures, typified by the four-way junction. These are the same structures favored by an abundant class of high mobility group proteins (HMG 1/2), and resemble the DNA structure at the entrance and exit from the nucleosome. Linker histones and HMG1 binding appear to be related to general mechanisms of genetic repression and expression. We propose a detailed investigation of this selective binding, including quantitation of binding by intact histones and their globular domains to the junction, and competition between histone variants and HMGI for such binding. The binding/competition experiments will then be extended to studies utilizing nucleosomes, as a more direct model of the in vivo structure. A second area of study will utilize PCR amplification methods in an attempt to discover DNA sequences or sequence types exhibiting strong linker histone binding. These will then be used in studies of the effects of such binding on DNA conformation.

我们实验室的最新证据表明，所谓的“连接子” 组蛋白（H1、H5 及其变体）可以结合某些 DNA 结构 并且序列比迄今为止所认为的更加具体。 在 特别是，这些组蛋白与 DNA 交叉结构强烈结合， 以四路交叉口为代表。 这些都是受青睐的相同结构 由丰富的高迁移率族蛋白 (HMG 1/2) 组成，以及 类似于核小体入口和出口处的 DNA 结构。 连接组蛋白和 HMG1 结合似乎与一般相关 基因抑制和表达的机制。我们提出了详细的 研究这种选择性结合，包括结合的定量 由完整的组蛋白及其球状结构域连接到连接处，并且 组蛋白变体和 HMGI 之间对这种结合的竞争。 这 然后结合/竞争实验将扩展到利用 核小体，作为体内结构的更直接的模型。 第二个研究领域将利用 PCR 扩增方法 尝试发现表现出强大的DNA序列或序列类型 接头组蛋白结合。 然后这些将用于研究效果 DNA构象上的这种结合。