Biochemical Basis of Chromatin Folding and Chromosome Condensation

项目摘要/摘要 PI研究计划的长期目标是阐明分子机制、结构和 染色质折叠和染色体凝聚的调节。追求根本的理由 对细胞核和染色体内DNA折叠的研究表明，在许多情况下，这种折叠出现了错误 人类疾病，如先天性肢体畸形、短指、F综合征和多指，以及 胶质瘤和T细胞急性淋巴细胞性白血病等癌症。基础研究，如建议的研究 在这里，需要充分定义这些疾病的病理生理学，并将作为开发的基础 特定的、有针对性的疗法。为了追求这一长期目标，本项目期间的目标是 定义最近发现的独立折叠的拓扑相关结构域(TADS)内的DNA折叠 染色质的结构域。TADs是染色质的区域，更有可能与自身相互作用，而不是与 其密度是完全延伸的“串珠”染色质纤维的30倍。 本项目期间的具体目标是：(1)确定影响TAD的染色质纤维的固有属性 折叠，(2)阐明DNA在TAD内的折叠模式，以及(3)阐明TAD结构是如何随着 细胞进入有丝分裂。这些目标将通过整合各种方法的创新的整体方法来实现 来自分子遗传学、分子生物学、细胞生物学和基因组学。这样做的预期结果是 综合方法是，拟议工作的完成将揭示DNA如何在TADS内折叠，以及如何 当细胞退出间期并进入中期时，这种折叠发生变化。这些结果将产生积极的影响 在染色体生物学领域，通过提供对染色质折叠和 染色体凝聚。这样的分子理解有望最终揭示 染色质折叠对基因调控和细胞遗传的影响。这一基本知识对于定义 人类疾病的病理生理学和开发新的治疗方法。

PROJECT SUMMARY/ABSTRACT The long-term goal of the PI’s research program is to elucidate the molecular mechanisms, structure, and regulation of chromatin folding and chromosome condensation. The rationale for pursuing fundamental investigations into DNA folding within nuclei and chromosomes is that this folding goes awry in a number of human diseases, such as the congenital limb malformations brachydactyly, F-syndrome, and polydactyly, and cancers such as glioma and T-cell acute lymphoblastic leukemia. Fundamental studies, such as those proposed here, are needed to fully define the pathophysiology of these diseases and will serve as a basis for developing specific, targeted therapeutics. In pursuit of this long-term goal, the objective during this project period is to define DNA folding within topologically associating domains (TADs), recently discovered independently folded domains of chromatin. TADs are regions of chromatin more likely to interact with themselves than with their neighbors, and are up to 30-fold more condensed than a fully extended, “beads-on-a-string” chromatin fiber. Specific aims for this project period are: (1) identify intrinsic properties of the chromatin fiber that affect TAD folding, (2) elucidate the folding pattern of DNA within a TAD, and (3) elucidate how TAD structure changes as cells enter mitosis. These aims will be attained using an innovative, holistic approach that integrates methods from molecular genetics, molecular biology, cell biology, and genomics. The expected outcomes of this combined approach is that completion of the proposed work will reveal how DNA is folded within TADs, and how this folding changes as cells exit interphase and enter metaphase. These outcomes will have a positive impact on the field of chromosome biology by providing a better molecular understanding of chromatin folding and chromosome condensation. Such a molecular understanding is expected to ultimately reveal the impact of chromatin folding on gene regulation and cellular heredity. This fundamental knowledge is necessary for defining the pathophysiology of human disease and developing novel therapeutics.