Cardiac interaction networks as determinants of transcriptional specificity

心脏相互作用网络作为转录特异性的决定因素

• 批准号: 10159116
• 负责人: Frank Leo Conlon
• 金额: $ 54.96万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2023-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10159116
• 关键词: Address; Atrial Heart Septal Defects; Binding Sites; Biochemical; Cardiac; Cardiac Myocytes; Cardiac development; Complex; Congenital Abnormality; Conserved Sequence; Coupled; Data; Deacetylase; Disease; Ectopic Expression; Embryo; Europe; Fibroblasts; GATA4 gene; Genes; Genetic; Genetic Transcription; Heart; Heart Abnormalities; Heart Septal Defects; Holt Oram syndrome; Homeostasis; Human; Infant Mortality; Lead; Molecular; Mus; Mutation; Nucleic Acid Regulatory Sequences; Nucleosomes; Pattern; Phase; Proteins; Proteomics; Repression; Role; Set protein; Specificity; Structural Congenital Anomalies; System; Testing; Time; Tissues; Transcription Coactivator; Transcriptional Regulation; Work; base; cardiogenesis; cell type; congenital heart disorder; gene repression; genetic corepressor; human disease; in vivo; insight; liquid chromatography mass spectrometry; novel; programs; protein complex; protein function; septal defect; transcription factor

ABSTRACT Congenital malformations, or structural birth defects, are now the leading cause of infant mortality in the US and Europe. Of the congenital malformations, congenital heart disease (CHD) is the most common. Mutations in the T-box transcription factor TBX5 have been found to be causative to a range of human cardiac abnormalities including Tetrology of Fallot and Holt Oram Syndrome (HOS), disease states associated associated with cardiac septal defects. While TBX5 is an essential transcription factor for heart development and its disease relevance is well established, there are many critical questions unanswered about the mechanism of how TBX5 functions. We do not understand what proteins complex with TBX5 during different stages of cardiac development and homeostasis, how these interactions regulate TBX5's choice of distinct transcriptional targets at different times, or how these interactions function to activate and/or repress target gene transcription. To this end, our labs recently initiated a directed proteomic-based approach to identify proteins that function in association with TBX5. These studies demonstrate TBX5 interacts with the transcriptional repression machinery of the Nucleosome Remodeling and Deacetylase (NuRD) complex. We further demonstrated that TBX5 human disease mutations disrupt this interaction, leading to ectopic expression of non-cardiac genes normally repressed by TBX5 and septal defects associated with Holt Oram syndrome. Collectively, this work led to the central hypothesis that TBX5 function and thus its suites of target genes are regulated during cardiac development through changes in the components of the TBX5 interactome. To address this hypothesis, we will used an integrated systems based approach to determine the mechanisms by which Tbx5 regulates distinct gene programs in the heart by defining the endogenous cardiac TBX5 transcriptional complexes, establish the mechanisms of TBX5 repression and activation and by determining the potential role of co-factors in TBX5 transcriptional regulation.

摘要 先天性畸形，或结构性出生缺陷，现在是婴儿死亡的主要原因， 美国和欧洲。在先天性畸形中，以先天性心脏病（CHD）最多 共同已经发现T盒转录因子TBX 5中的突变是导致 一系列人类心脏异常，包括法洛四联症和Holt Oram综合征（HOS）， 与心脏间隔缺损相关的疾病状态。虽然TBX 5是一个重要的 心脏发育的转录因子及其疾病相关性已经很好地建立， 关于TBX 5如何发挥作用的机制，还有许多关键问题没有得到解答。我们不 了解在心脏发育的不同阶段，哪些蛋白质与TBX 5复合， 稳态，这些相互作用如何调节TBX 5对不同转录靶点的选择， 不同的时间，或者这些相互作用如何起作用以激活和/或抑制靶基因转录。 为此，我们的实验室最近启动了一种基于定向蛋白质组学的方法来鉴定蛋白质， 与TBX 5相关。这些研究表明TBX 5与转录因子相互作用， 核小体重塑和脱乙酰酶（NuRD）复合物的抑制机制。我们进一步 证明TBX 5人类疾病突变破坏了这种相互作用，导致异位 TBX 5正常抑制的非心脏基因表达和与Holt相关的间隔缺损 奥拉姆综合征。总的来说，这项工作导致了中心假设，即TBX 5的功能，因此其 在心脏发育过程中，靶基因组通过组分的变化受到调节， TBX 5相互作用组的基因。为了解决这个假设，我们将使用一个集成的系统， 确定Tbx 5调节心脏不同基因程序的机制的方法 通过定义内源性心脏TBX 5转录复合物，建立 TBX 5抑制和激活以及通过确定辅助因子在TBX 5抑制和激活中的潜在作用， 转录调控