Transcriptional Networks During Cardiac Differentiation

描述（由申请人提供）： 信号传导、转录和转录后事件调节早期心脏发生过程中心脏细胞的命运决定。此类事件的破坏可能导致先天性心脏畸形。特别是，人类转录因子 (TF)（例如 GATA4、TBX5、NKX2-5 和 N0TCH1）突变会导致儿童心脏病。成人心脏中的胚胎通路在压力下重新激活，GATA4 和 MEF2C 在心脏肥大期间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 TF 转录输出方面的重要性。然而，尚未系统地探索可滴定心脏 TF 效应的复杂 PPI。在该 PPG 的上一个资助期间，我们的发现集中于各种信号传导和转录事件的影响，这些事件常常最终导致 TF 和染色质重塑复合物之间的组合相互作用来调节心脏基因表达。例如，对心脏发育转录因子（包括 Gata4、Mef2c 和 Tbx5）和染色质重塑蛋白（例如 Baf60c）进行组合操作，可以诱导非肌肉细胞重编程为心肌细胞样细胞，并促进损伤后的心脏再生。随着心脏细胞中全基因组 TF 结合数据的积累，我们必须了解调节蛋白的复杂组合相互作用，以解释 DNA 结合的转录后果。在这里，我们将利用几位心脏转录因子方面的国际专家、领先的系统生物学家的专业知识和计算生物学的优势，系统地确定复杂的相互作用组，核心心脏转录机制通过这些相互作用来调节心脏分化过程中的基因表达。提出了三个独立的项目来深入探讨由拟议的蛋白质组学核心确定的选定相互作用组的功能结果。细胞生产核心中源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，数据将由拟议的生物信息学核心进行分析并与其他增强子和染色质数据整合。

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.