Transcriptional Networks During Cardiac Differentiation

描述（由申请人提供）： 信号传导、转录和转录后事件在早期心脏发生过程中调节心脏细胞的命运决定。这些事件的中断可能导致先天性心脏畸形。特别是，转录因子（TF）中的人类突变，如GATA 4，TBX 5，NKX 2 -5和NOTCH 1，导致儿童心脏病。胚胎途径在成年心脏的应激下被重新激活，其中GATA 4和MEF 2C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结合转录因子的转录输出中的重要性。然而，尚未系统探索滴定心脏TF效应的复杂PPI。在PPG的上一个资助期间，我们的发现集中在各种信号和转录事件的影响上，这些事件经常导致TF和染色质重塑复合物之间的组合相互作用，以调节心脏基因表达。例如，操纵心脏发育TF（包括Gata 4、Mef 2c和Tbx 5）和染色质重塑蛋白（例如，Baf 60 c），可诱导非肌细胞重编程为心肌样细胞，促进损伤后心脏再生。随着心脏细胞全基因组TF结合数据的积累，我们必须了解调控蛋白的复杂组合相互作用，以解释DNA结合的转录后果。在这里，我们将利用心脏转录因子，领先的系统生物学家和计算生物学优势的几个国际专家的专业知识，系统地确定复杂的相互作用，通过它的核心心脏转录机制的功能，以调节心脏分化过程中的基因表达。提出了三个离散的项目，以深入询问所选择的相互作用决定的建议蛋白质组学核心的功能后果。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，数据将通过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.