Transcriptional Networks During Cardiac Differentiation

描述(由申请人提供)： 信号、转录和转录后事件调节心脏细胞在早期心脏发生过程中的命运决定。这类事件的中断可能会导致先天性心脏畸形。特别是，人类转录因子(TF)的突变，如GATA4、TBX5、NKX2-5和N0TCH1，会导致儿童心脏病。在成年心脏中，胚胎通路在应激条件下被重新激活，GATA4和MEF2C在心肌肥厚时的转录反应中发挥核心作用。最近的研究强调了蛋白质-蛋白质相互作用(PPI)在决定心脏DNA结合转录因子的转录输出中的重要性。然而，滴定心脏转录因子效应的复杂的PPI还没有被系统地探索。在该PPG的前一次资助期间，我们的发现主要集中在各种信号和转录事件的影响上，这些事件往往最终导致TF和染色质重塑复合体之间的组合相互作用，以调节心脏基因的表达。例如，操作心脏发育因子，包括Gata4、MEF2C和Tbx5，以及染色质重塑蛋白(例如，BAF60c)，可以诱导非肌肉细胞重新编程为心肌细胞样细胞，并促进损伤后的心脏再生。随着全基因组转录因子结合数据在心肌细胞中的积累，我们必须了解调控蛋白的复杂组合相互作用，以解释DNA结合的转录结果。在这里，我们将利用几位心脏转录因子方面的国际专家的专业知识，一位领先的系统生物学家，以及计算生物学的优势，系统地确定心脏核心转录机制在心脏分化过程中调节基因表达的复杂相互作用。三个离散的项目被提出，以深入询问由拟议的蛋白质组学核心确定的选定相互作用的功能后果。细胞生产核心中来自小鼠胚胎干细胞的心脏祖细胞和心肌细胞将用于蛋白质组学研究，数据将通过拟议的生物信息学核心与其他增强子和染色质数据进行分析和整合。

DESCRIPTION (Provided by applicant): Signaling, transcriptional, and post-transcriptional events regulate cardiac cell fate decisions during early cardiogenesis. Disruption of such events can lead to congenital heart malformations. In particular, human mutations in transcription factors (TFs), such as GATA4, TBX5, NKX2-5 and N0TCH1, result in heart disease in children. Embryonic pathways are reactivated under stress in adult hearts, with GATA4 and MEF2C playing central roles in the transcriptional response during cardiac hypertrophy. Recent studies highlight the importance of protein-protein interactions (PPI) in dictating the transcriptional output of cardiac DNA-binding TFs. However, the complex PPIs that titrate effects of cardiac TFs have not been systematically explored. During the previous funding period of this PPG, our discoveries focused on the effects of a variety of signaling and transcriptional events that frequently culminated in combinatorial interactions between TFs and chromatin remodeling complexes to regulate cardiac gene expression. For example, manipulation of a combination of cardiac developmental TFs, including Gata4, Mef2c and Tbx5, and chromatin remodeling proteins (e.g., Baf60c), could induce the reprogramming of non-muscle cells into cardiomyocyte-like cells and promote cardiac regeneration after injury. As genome-wide TF binding data in cardiac cells accumulate, it is imperative that we understand the complex combinatorial interactions of regulatory proteins to interpret the transcriptional consequences of DNA-binding. Here, we will leverage the expertise of several of the international experts in cardiac transcription factors, a leading systems biologist, and computational biology strengths to systematically determine the complex interactomes by which the core cardiac transcriptional machinery functions to regulate gene expression during cardiac differentiation. Three discrete projects are proposed to deeply interrogate the functional consequence of selected interactomes determined by the proposed Proteomics Core. Cardiac progenitors and cardiomyocytes derived from mouse embryonic stem cells in the Cell Production Core will be used for the proteomic studies and data will be analyzed and integrated with other enhancer and chromatin data by the proposed Bioinformatics Core.