Mechanisms underlying YY1 control of intestinal epithelial homeostasis

YY1控制肠上皮稳态的机制

• 批准号: 8689012
• 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/8689012
• 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(申请人提供)：在肠上皮中，调节增殖和分化之间的平衡行为的调节机制尚未完全确定，但对于维持正常的动态平衡和疾病的恢复至关重要。肠上皮的动态平衡需要精确的调控：过度的增殖会导致肿瘤的形成，但增殖不足会导致组织崩溃。这项应用的目的是通过研究一种意想不到的转录因子在这一过程中的重要作用来弥合我们对肠道内稳态的理解上的差距。初步研究表明，成年小鼠肠上皮中转录因子YY1的失活引发了严重的上皮内稳态失衡：祖细胞种群扩大，而分化的种群收缩。因此，明确YY1如何控制上皮细胞周转可能为恢复疾病中上皮细胞的动态平衡提供一个新的治疗切入点。这个项目的第一个目标是测试3个合理的、非排他性的解释 对于缺乏YY1的肠上皮中增殖的隐窝细胞的增加：1)YY1控制干细胞周转，2)YY1控制隐窝细胞的增殖，或3)YY1介导细胞周期停滞和终末分化。小鼠的遗传学和组织学方法将测量YY1缺失时上皮细胞的数量和行为。完成这一目标应该确定YY1维持内环境平衡的具体过程。该项目的第二个目标将确定YY1‘S控制上皮周转的转录调控机制。CHIP-SEQ将被用于绘制YY1与分离的肠上皮细胞群体基因组的相互作用图。确定YY1的S基因组结合位置将有助于我们确定其直接调控靶基因，确定其调控伙伴转录因子，并确定YY1是在活性染色质结构中工作还是在抑制染色质结构中工作。这些分析将与YY1基因敲除的基因表达分析相结合，并得到从当前K01收集的染色质芯片序列数据的补充。这项拟议的研究具有创新性，因为它有望揭示一种新的、依赖于YY1的调控机制，通过使用尖端的表观基因组技术来控制增殖/分化决策。这项拟议工作的完成将揭示体内平衡细胞周转的新机制，并对伤口愈合和肿瘤发生等不同领域具有重要价值。最后，正如这个R03机制的目的一样，资助这个项目应该会增强K01奖获得者进行研究的能力。建立新的调查人员加入抗击肠道疾病的斗争是NIDDK的优先事项，这是解决该国最大的医疗问题之一的长期目标的一部分。拟议中的YY1调控机制研究非常适合这一目的，因为它可以在短时间内完成，但我可能会打开一个新的研究领域，研究肠上皮更新的机制。