NUCLEAR MATRIX STRUCTURES AND GENOMIC FUNCTION

核基质结构和基因组功能

• 批准号: 6199000
• 负责人: Ronald Berezney
• 金额: $ 35.19万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 1977
• 资助国家: 美国
• 起止时间: 1977-09-30 至 2004-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6199000
• 关键词: DNA replication; DNA replication origin; affinity chromatography; bioimaging /biomedical imaging; cell component structure /function; cell nucleus; chick embryo; digital imaging; functional /structural genomics; imaging /visualization /scanning; laboratory mouse; laboratory rat; microscopy; nuclear matrix; nucleoproteins; protein structure function; structural biology; tissue /cell culture

The cell nucleus is the repository for the genetic information of all eucaryotic cells including those of man. Despite considerable progress in defining basic molecular properties of the primary genomic functions of DNA replication, transcription, and RNA splicing and processing, our knowledge of how these processes are organized and coordinated within the confines of the functional cell nucleus has been until recently very limited. Impressive progress in applying molecular probes along with developments in 3-D microscopy and computer image analysis is rapidly correcting this deficiently and is leading to a new view of the cell nucleus based on the functional dynamics of nuclear architecture. In situ labeling coupled with three dimensional microscopy and computer imaging techniques reveal that DNA replication and transcription sites are organized into higher order units or "zones" in the cell nucleus. The dynamic interplay and "re-zoning" of replication and transcription regions during the cell cycle may form the structural basis for the elaborate global coordination of replicational and transcriptional programs in the mammalian cell. As one basis for this functional organization, the genome is arranged in discrete chromosome territories in the interphase nucleus. This organization is strikingly maintained following extraction of cells for nuclear matrix under conditions which maintained the DNA intact. Appropriate extraction of the nuclear matrix internal components leads to a corresponding disruption of chromosome territories along with the release of a discrete subset of proteins that are candidates for being chromosome territory anchoring proteins. With these previous studies as a basis we propose the following specific aims: (1) Further develop multi-dimensional computer imaging approaches to 3-D microscopy; (2) Elucidate the 3-D spatio-temporal properties of DNA replication and transcription sites for genes replicating in early S-phase; (3) Study chromosome territories in relations to higher order domains of DNA replication and transcription sites and characterize candidate chromosome territory anchor proteins; (4) Investigate the 3-D dynamics of DNA replication and transcription sites in living cells.

细胞核是包括人类在内的所有真核细胞遗传信息的储存库。 尽管在定义 DNA 复制、转录、RNA 剪接和加工等主要基因组功能的基本分子特性方面取得了相当大的进展，但直到最近，我们对这些过程如何在功能性细胞核范围内组织和协调的知识仍然非常有限。分子探针应用方面取得的令人印象深刻的进展以及 3D 显微镜和计算机图像分析的发展正在迅速纠正这一缺陷，并带来基于核结构功能动力学的细胞核新观点。 原位标记结合三维显微镜和计算机成像技术揭示了 DNA 复制和转录位点在细胞核中组织成更高阶的单元或“区域”。 细胞周期中复制和转录区域的动态相互作用和“重新分区”可能构成哺乳动物细胞中复制和转录程序的精细全局协调的结构基础。 作为这种功能组织的基础，基因组排列在间期核中离散的染色体区域中。 在保持 DNA 完整的条件下提取细胞核基质后，这种组织得到了惊人的维持。 核基质内部成分的适当提取导致染色体区域的相应破坏，同时释放作为染色体区域锚定蛋白的候选蛋白质的离散子集。 以这些先前的研究为基础，我们提出以下具体目标：（1）进一步开发3D显微镜的多维计算机成像方法； (2) 阐明早期S期基因复制的DNA复制和转录位点的3-D时空特性； (3) 研究染色体区域与DNA复制和转录位点的高阶结构域的关系，并表征候选染色体区域锚定蛋白； (4) 研究活细胞中 DNA 复制和转录位点的 3-D 动态。