Cohesin Polycomb Interactions in Gene Regulation

基因调控中的粘连蛋白多梳相互作用

基本信息

批准号：
8990016
负责人：
Dale L Dorsett
金额：
$ 29.63万
依托单位：
SAINT LOUIS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-01-01 至 2017-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8990016
关键词：
Affinity Chromatography Amino Acids Binding Biochemical Biochemical Genetics Bruck-de Lange syndrome Cancer Prognosis Cell division Cells Chromatids Chromosome Segregation Chromosomes Complex Data Defect Development Diagnosis Drosophila genus Ensure Epigenetic Process Equilibrium Excision Fluorescence Recovery After Photobleaching Gene Expression Gene Expression Regulation Gene Silencing Genes Genetic Genetic Transcription Genomic approach Genomics Goals Growth Growth and Development function Health Histones Human Genetics Individual Knowledge Link Malignant Neoplasms Maps Messenger RNA Methods Modeling Molecular Mutation Organism PRC1 Protein Patients Phosphotransferases Polycomb Polymerase Positive Transcriptional Elongation Factor B Properdin Proteins Prothrombin Proto-Oncogenes RNA Polymerase II Recruitment Activity Role Sister Chromatid Syndrome Testing Transcription Initiation Site Work base biophysical techniques chromatin immunoprecipitation cohesin cohesion developmental disease genetic approach global run on sequencing human disease in vivo insight negative elongation factor novel outcome forecast premature prevent promoter research study tool tumor tumor growth

项目摘要

DESCRIPTION (provided by applicant): The long-term goal of the proposed work is to determine how sister chromatid cohesion proteins control gene transcription. This will illuminate mechanisms that underlie certain human genetic syndromes and cancers. Cohesin topologically encircles sister chromatids to hold them together until a cell divides. Moderate reductions in cohesin activity don't disrupt chromatid cohesion, but alter gene transcription, leading to poor growth and development. High cohesin activity is linked to poor prognosis in multiple cancers. How cohesin controls transcription is largely unknown, but current evidence argues that it participates directly in multiple mechanisms. Recent discoveries argue for a new paradigm in which a balance between cohesin and the Polycomb Repressive Complex 1 (PRC1) epigenetic silencing complex globally controls both gene silencing and transcription of many active genes. The data argue that cohesin directly facilitates binding of PRC1 to active genes, where PRC1 prevents paused RNA polymerase II (Pol II) at the promoter from prematurely entering into elongation. They also suggest that cohesin at active genes sequesters PRC1, thereby controlling how much is available for gene silencing, and that PRC1 limits cohesin binding at silenced and active genes. The goal of this proposal is to test this new paradigm, and determine the mechanisms by which cohesin and PRC1 together control both gene silencing and transcription of active genes. The proposed studies combine biochemical, genetic, genomic, and biophysical approaches to test key predictions of the current model. Aim 1 tests the ideas that cohesin physically interacts with PRC1 to directly facilitate PRC1 binding to active gene promoters, and that PRC1 limits cohesin binding through interactions with cohesin loading or removal factors. Aim 2 tests the idea that PRC1 prevents premature entry of paused Pol II into elongation by facilitating NELF and DSIF pausing factor or Pol II kinase activities. The insights into the mechanisms by which cohesin and PRC1 control transcription provided by these studies should suggest new methods for correcting cohesin-PRC1 imbalances in genetic syndromes and cancer.

描述（由申请人提供）：拟议工作的长期目标是确定姐妹染色单体粘合蛋白如何控制基因转录。这将阐明某些人类遗传综合症和癌症的机制。粘连蛋白在拓扑上环绕姐妹染色单体，将它们保持在一起，直到细胞分裂。粘连蛋白活性的适度降低不会破坏染色单体的粘连，但会改变基因转录，导致生长和发育不良。高粘连蛋白活性与多种癌症的不良预后有关。粘连蛋白如何控制转录在很大程度上尚不清楚，但目前的证据表明它直接参与多种机制。最近的发现提出了一种新的范式，其中粘连蛋白和多梳抑制复合物 1 (PRC1) 表观遗传沉默复合物之间的平衡全局控制着许多活性基因的基因沉默和转录。数据表明，粘连蛋白直接促进 PRC1 与活性基因的结合，其中 PRC1 防止启动子处暂停的 RNA 聚合酶 II (Pol II) 过早进入延伸。他们还表明，活性基因上的粘连蛋白会隔离 PRC1，从而控制可用于基因沉默的量，并且 PRC1 限制了沉默基因和活性基因上的粘连蛋白结合。该提案的目标是测试这种新范例，并确定粘连蛋白和 PRC1 共同控制基因沉默和活性基因转录的机制。拟议的研究结合了生物化学、遗传学、基因组和生物物理方法来测试当前模型的关键预测。目标 1 测试了粘连蛋白与 PRC1 物理相互作用以直接促进 PRC1 与活性基因启动子结合，以及 PRC1 通过与粘连蛋白加载或去除因子相互作用来限制粘连蛋白结合的想法。目标 2 测试了 PRC1 通过促进 NELF 和 DSIF 暂停因子或 Pol II 激酶活性来防止暂停的 Pol II 过早进入伸长的想法。这些研究提供的对粘连蛋白和 PRC1 控制转录机制的见解应该提出纠正遗传综合征和癌症中粘连蛋白-PRC1 失衡的新方法。