Mechanisms underlying YY1 control of intestinal epithelial homeostasis

YY1控制肠上皮稳态的机制

• 批准号: 8565630
• 负责人: MICHAEL P. VERZI
• 金额: $ 7.75万
• 依托单位: RUTGERS, THE STATE UNIV OF N.J.
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2015-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8565630
• 关键词: Ablation; Adult; Alkaline Phosphatase; Area; Behavior; Binding; Cell Count; Cell Cycle Arrest; Cell Differentiation process; Cell Lineage; Cell Proliferation; Cells; ChIP-seq; Chromatin; Chromatin Structure; Complement; Contracts; Country; Data; Data Set; Differentiation Antigens; Disease; Duodenum; Embryo; Epithelial; Epithelial Cells; Equilibrium; Event; Funding Mechanisms; Gene Expression; Gene Expression Profiling; Gene Targeting; Genes; Genetic; Genome; Genomics; Goals; Health; Homeostasis; Intestinal Diseases; Intestines; Knock-out; Knowledge; Lead; Length; Location; Maps; Measures; Mediating; Medical; Mentored Research Scientist Development Award; Molecular; Mus; Mutant Strains Mice; National Institute of Diabetes and Digestive and Kidney Diseases; Population; Process; Proliferating; Public Health; Recovery; Regulation; Research; Research Personnel; Role; Staining method; Stains; Stem cells; Technology; Testing; Therapeutic Intervention; Tissues; Villus; Work; Wound Healing; YY1 Transcription Factor; absorption; base; crypt cell; embryonic stem cell; epigenomics; fight against; innovation; intestinal epithelium; intestinal homeostasis; jejunum; novel; novel therapeutics; progenitor; public health relevance; skeletal; transcription factor; tumor; tumorigenesis; villin

DESCRIPTION (provided by applicant): In the intestinal epithelium, the regulatory mechanisms that mediate the balancing act between proliferation and differentiation are incompletely defined, but are critical for maintaining normal homeostasis and its recovery from disease. Intestinal epithelial homoeostasis requires precise regulation: excess proliferation can lead to tumor formation, but insufficient proliferation would cause tissue collapse. The objective of this application is to bridge the gap in our understanding of intestinal homeostasis by investigating an unexpected transcription factor's essential role in this process. Preliminary studies show that inactivation of the transcription factor YY1 in the adult murine intestinal epithelium triggers massive imbalance of epithelial homeostasis: the progenitor population expands while the differentiated population contracts. Therefore, defining how YY1 controls epithelial turnover could provide a novel therapeutic entry point in restoring epithelial homeostasis in disease. This project's first Aim is to test 3 plausible, non-exclusive explanations for the increase in proliferating crypt cells in intestinal epithelia lacking YY1: 1) YY1 controls stem cell turnover, 2) YY1 controls crypt cell proliferation, or 3) YY1 mediates cell cycle arrest and terminal differentiation. Mouse genetic and histological approaches will measure epithelial cell populations and behaviors upon YY1 loss. Completion of this aim should define the specific process(es) by which YY1 maintains homeostatic balance. The second Aim of the project will define the transcriptional regulatory mechanisms underlying YY1's control of epithelial turnover. ChIP-seq will be employed to map YY1 interactions with the genome of isolated intestinal epithelial cell populations. Identification of YY1's genomic binding locations will allow us to identify its direct regulatory target genes, identify its regulatory partner transcription factors,and determine whether YY1 operates in active or repressed chromatin structure. These analyses will be integrated with gene expression analysis of the YY1 knockout, and complemented by chromatin ChIP-seq data collected from the current K01. The proposed research is innovative in that it is expected to reveal a novel, YY1-dependent regulatory mechanism governing the proliferation/differentiation decision by using cutting-edge epigenomic technologies. Completion of the proposed work will reveal new mechanisms underlying homeostatic cell turnover and should be of significant value to fields as diverse as wound healing and oncogenesis. Finally, as is intended for this R03 mechanism, funding this project should enhance the capability of the K01-awarded investigator to conduct research. Establishing new investigators to join the fight against intestinal disease is a priority for the NIDDK as part of a long-term goal to solve one of the Country's largest medical problems. The proposed research on the regulatory mechanisms of YY1 is perfectly suited for this purpose in that it can be completed in a short timeframe, yet i likely to open a new area of research on the mechanisms of intestinal epithelial renewal.

描述（由申请人提供）：在肠上皮中，介导增殖和分化之间平衡作用的调节机制尚未完全确定，但对于维持正常的体内平衡及其从疾病中恢复至关重要。肠上皮稳态需要精确调节：过度增殖会导致肿瘤形成，但增殖不足会导致组织崩溃。该应用的目的是通过研究意想不到的转录因子在此过程中的重要作用来弥补我们对肠道稳态的理解差距。初步研究表明，成年小鼠肠上皮中转录因子YY1的失活会引发上皮稳态的严重失衡：祖细胞群体扩张，而分化群体收缩。因此，定义 YY1 如何控制上皮更新可以为恢复疾病中的上皮稳态提供新的治疗切入点。该项目的第一个目标是测试 3 个似是而非的非排他性解释 对于缺乏 YY1 的肠上皮中隐窝细胞增殖的增加：1）YY1 控制干细胞周转，2）YY1 控制隐窝细胞增殖，或 3）YY1 介导细胞周期停滞和终末分化。小鼠遗传学和组织学方法将测量 YY1 丢失后的上皮细胞群和行为。完成这一目标应定义 YY1 维持稳态平衡的具体过程。该项目的第二个目标将确定 YY1 控制上皮更新的转录调控机制。 ChIP-seq 将用于绘制 YY1 与分离的肠上皮细胞群基因组的相互作用图谱。鉴定 YY1 的基因组结合位置将使我们能够鉴定其直接调控靶基因，鉴定其调控伙伴转录因子，并确定 YY1 是否在活跃或抑制的染色质结构中运作。这些分析将与 YY1 敲除的基因表达分析相结合，并由从当前 K01 收集的染色质 ChIP-seq 数据进行补充。拟议的研究具有创新性，因为它有望通过使用尖端表观基因组技术揭示一种新颖的、YY1依赖性的调控机制来控制增殖/分化决策。完成拟议的工作将揭示稳态细胞更新的新机制，并且对伤口愈合和肿瘤发生等不同领域具有重要价值。最后，正如 R03 机制的目的一样，资助该项目应能增强 K01 授予的研究者进行研究的能力。建立新的研究人员来参与对抗肠道疾病是 NIDDK 的首要任务，也是解决该国最大的医疗问题之一的长期目标的一部分。所提出的关于YY1调节机制的研究非常适合这个目的，因为它可以在短时间内完成，但我可能会开辟一个关于肠上皮更新机制的新研究领域。