Defining the role of Pou6f1 in cardiac morphogenesis

明确Pou 6 f1在心脏形态发生中的作用 项目摘要 先天性心脏病（CHD）是导致出生缺陷的主要原因， 尽管现代管理有明显改善，但预后良好。这一失误源于严重的... 缺乏诊断能力，加上完全不能改变潜在的疾病过程。替代- 尽管负责心脏发育的转录途径已经得到了很好的表征， 迫切需要已建立的电路的调节器来识别新的CHD候选基因座， 潜在的治疗靶点。这项研究计划的长期目标是了解转录条件， 使用房室通道（AVC）分化作为模型系统来控制心脏谱系特化。的 该建议的目的是表征最近确定的AVC规范的上游调节器。我们 中心假设是Pou 6 f1调节心脏结构和功能。为了验证这一假设，我们建议 以下具体目的：1）分析由Pou 6 f1过表达引起的心脏表型，和2）去- 探讨Pou 6 f1基因缺失对心功能的影响。我们的初步数据表明，心脏特异性 显性负性Pou 6 f1的过表达扰乱AVC形态发生并导致胚胎死亡。 在目标1中，我们将通过使用Pou 6 f1基因来研究心脏发育过程中Pou 6 f1功能获得的后果。 我们在实验室中产生的两个组织特异性Pou 6 f1过表达的小鼠品系。额外预 初步结果表明，Pou 6 f1基因缺失导致男性特异性胚胎致死和心肌病 幸存的女性。在目标2中，我们将评估整体和心脏特异性 使用我们先前获得的floxed等位基因进行Pou 6 f1缺失。我们的方法是创新的，因为它 将挑战和扩展现有的AVC形态发生的范例，这是正确形成 房间隔、室间隔和AV瓣膜。这个项目意义重大，因为它意味着- 在AVC特化和心脏形态发生中发现一个全新的转录途径。总的来说- 呃，从拟议的研究中预期的好处是建立Pou 6 f1在心脏形态学中的作用， 起源，并获得竞争性R 01提交的关键初步数据。我们预计， 后续研究将提供对AVC形态发生的更有根据的机制理解。反过来， 这些见解有望扩大候选基因座的名单，并为合理设计新的基因座提供平台。 治疗AVSD。

Defining the role of Pou6f1 in cardiac morphogenesis PROJECT SUMMARY Congenital heart disease (CHD) is the leading cause of birth defects and continues to carry a poor long-term prognosis despite marked improvements in contemporary management. This failure stems from severely lim- ited diagnostic capabilities coupled with a complete inability to modify the underlying disease process. Alt- hough the transcriptional pathways responsible for heart development have been well-characterized, new regulators of the established circuitry are urgently needed to identify novel CHD candidate loci and illuminate potential therapeutic targets. The long-term goal of this research program is to understand transcriptional con- trol of cardiac lineage specification using atrioventricular canal (AVC) differentiation as a model system. The objective of this proposal is to characterize a recently identified upstream regulator of AVC specification. Our central hypothesis is that Pou6f1 regulates cardiac structure and function. To test this hypothesis, we propose the following specific aims: 1) Analyze cardiac phenotypes resulting from Pou6f1 over-expression and 2) De- termine the impact of Pou6f1 deletion on cardiac function. Our preliminary data indicate that cardiac-specific over-expression of dominant-negative Pou6f1 perturbs AVC morphogenesis and results in embryonic lethality. In Aim 1, we will examine the consequences of Pou6f1 gain-of-function during heart development by utilizing two mouse lines for tissue-specific Pou6f1 over-expression that we have generated in our lab. Additional pre- liminary results show that global Pou6f1 deletion causes male-specific embryonic lethality and cardiomyopathy in surviving females. In Aim 2, we will evaluate the functional consequences of global and cardiac-specific Pou6f1 deletion using a floxed allele that we have previously obtained. Our approach is innovative because it will challenge and expand the existing paradigm for AVC morphogenesis, a critical step for proper formation of the atrial septum, ventricular septum, and AV valves. This project is significant, therefore, because it will impli- cate an entirely new transcriptional pathway in AVC specification and cardiac morphogenesis. Taken togeth- er, the expected benefits from the proposed studies are to establish a role for Pou6f1 during cardiac morpho- genesis and to obtain key preliminary data for a competitive R01 submission. We anticipate that subsequent follow-up studies will provide a more informed mechanistic understanding of AVC morphogenesis. In turn, such insights promise to expand the list of candidate loci and provide a platform for the rational design of novel treatments for AVSDs.