Exploring novel regulatory mechanisms underlying enhancer activation and cell fate transition

探索增强子激活和细胞命运转变的新调控机制

基本信息

批准号：
10471972
负责人：
Kaixiang Cao
金额：
$ 17.36万
依托单位：
CASE WESTERN RESERVE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-08 至 2023-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10471972
关键词：
3-Dimensional Animals Architecture Award Binding Binding Proteins Biochemistry Bioinformatics Biological Assay Biology Bruck-de Lange syndrome CRISPR screen Cell Differentiation process Cell Maintenance Cells Chromatin Chromatin Structure Data Deposition Development Disease Dose Down-Regulation ES Cell Line Educational workshop Embryonic Development Enhancers Ensure Environment Enzymes Epigenetic Process Equilibrium Family Gene Expression Genes Genetic Transcription Genome Genomic approach Goals Grant Hi-C Higher Order Chromatin Structure Histone H3 Human Instruction KDM1A gene Kabuki Make-Up Syndrome Knock-out Lead Leadership Lysine Malignant Neoplasms Mentors Methylation Modeling Molecular Mutation Names Output Pathogenesis Pathology Pathway interactions Phase Play Pluripotent Stem Cells Postdoctoral Fellow Process Proteomics Regulation Research Role SET Domain Stem Cell Factor Testing Thalassemia Training Transcriptional Regulation Universities Writing antagonist base cancer type career career development chromosome conformation capture clinical application course development developmental disease driver mutation embryonic stem cell experience genetic corepressor genome wide screen genome-wide graduate student high throughput screening histone methyltransferase human disease inhibitor innovation insight loss of function loss of function mutation medical schools member new therapeutic target novel pluripotency programs protein complex recruit skills stem cell biology stem cell differentiation stem cells targeted treatment therapy development transcription factor transcriptome

项目摘要

Project Summary/Abstract Misregulation of enhancer activity leads to various developmental disorders including thalassemia, Cornelia de Lange syndrome, and Kabuki syndrome. The major enhancer regulator Mll4 belongs to the family of the Su(var)3- 9, Enhancer-of-zeste, Trithorax (SET) domain containing histone methyltransferases named COMplex of Proteins ASsociated with Set1 (COMPASS), which places methylation marks at lysine 4 of histone H3 (H3K4). Mll4 is essential for mammalian development and its heterozygous loss-of-function mutations lead to various human diseases including Kabuki syndrome and cancer. I recently demonstrated that Mll4 is the major enzyme depositing mono-methylation at H3K4 (H3K4me1), an enhancer-decorating epigenetic mark whose function remains elusive. Moreover, I have defined catalytic activity dependent and independent functions of Mll4 in enhancer modulation and stem cell differentiation, and have unveiled an antagonism between enhancer-binding epigenetic machineries in transcriptional control that could underlie the developmental consequences of the heterozygous loss-of-function mutations of Mll4 in human disease. Based on these findings, I hypothesize that Mll4 cooperates with key transcription factors and epigenetic modifiers to modulate enhancer activity, chromatin structure, and transcriptional outputs during stem cell maintenance and differentiation. The studies proposed here aim to elucidate the molecular mechanisms of enhancer regulation, and to provide insights for developing novel therapies targeting diseases driven by the loss of function of epigenetic modifiers. Specifically, the outlined research will 1) elucidate how epigenetic marks impact enhancer functions and cell fate transition; 2) determine the role of higher order chromatin structure in stem cell maintenance and differentiation; 3) identify novel factors and pathways involved in modulating enhancer activity and determining cell fate. To achieve the long-term career goal of defining the epigenetic mechanisms underlying mammalian development and disease, I will acquire training in biochemistry, proteomics, bioinformatics, stem cell biology, and genome-wide screening during the mentored phase of this application. Moreover, I will participate in grant writing workshops and career development courses to strengthen my skills in writing and leadership. With the acquired training, I will be well- prepared for the task of delineating the machineries and mechanisms in modulating gene expression, chromatin structure, and cell fate determination in the independent R00 phase. In summary, the K99/R00 award, together with the experiences that I have garnered as a graduate student and postdoc, the guidance from the mentors and collaborators, and the superb research environment at Northwestern University's Feinberg School of Medicine, will ensure a successful transition for me to continue my independent scientific career in the field of stem cell biology and epigenetics.

项目概要/摘要增强子活性的失调会导致各种发育障碍，包括地中海贫血、Cornelia de 兰格综合症和歌舞伎综合症。主要增强子调节因子 Mll4 属于 Su(var)3- 家族 9、Enhancer-of-zeste、Trithorax (SET) 结构域，含有名为 COMplex of 的组蛋白甲基转移酶与 Set1 (COMPASS) 相关的蛋白质，将甲基化标记置于组蛋白 H3 (H3K4) 的赖氨酸 4 处。 Mll4 对于哺乳动物的发育至关重要，其杂合的功能丧失突变导致各种人类疾病，包括歌舞伎综合症和癌症。我最近证明 Mll4 是主要酶在 H3K4 (H3K4me1) 上沉积单甲基化，这是一种增强子修饰的表观遗传标记，其功能仍然难以捉摸。此外，我定义了 Mll4 的催化活性依赖和独立功能增强子调节和干细胞分化，并揭示了增强子结合之间的拮抗作用转录控制中的表观遗传机制可能是发育后果的基础人类疾病中 Mll4 的杂合功能丧失突变。根据这些发现，我假设 Mll4 与关键转录因子和表观遗传修饰剂合作调节增强子活性、染色质干细胞维持和分化过程中的结构和转录输出。提出的研究这里的目的是阐明增强子调控的分子机制，并为开发提供见解。针对由表观遗传修饰剂功能丧失引起的疾病的新疗法。具体来说，概述了研究将1）阐明表观遗传标记如何影响增强子功能和细胞命运转变； 2）确定高阶染色质结构在干细胞维持和分化中的作用； 3）识别新因素以及参与调节增强子活性和决定细胞命运的途径。实现长远的职业生涯定义哺乳动物发育和疾病背后的表观遗传机制的目标，我将获得生物化学、蛋白质组学、生物信息学、干细胞生物学和全基因组筛选培训此应用程序的指导阶段。此外，我将参加资助写作研讨会和职业生涯发展课程，以加强我的写作和领导技能。通过获得的训练，我会很好- 为描绘调节基因表达、染色质的机器和机制的任务做好准备结构和独立R00期细胞命运的决定。综上所述，K99/R00奖，一起凭借我作为研究生和博士后所获得的经验，导师的指导和合作者，以及西北大学范伯格学院一流的研究环境医学，将确保我成功过渡，继续我在医学领域的独立科学事业干细胞生物学和表观遗传学。