Transcriptional Programming in the Maintenance and Commitment of Nephron Progenitors

项目摘要 美国约有490万成年人患有肾脏疾病。目前的治疗方法并不能治愈 终末期肾病的治疗。再生肾病有望开发新的治疗方法 战略。肾的功能单位是肾单位，它来自一个不同的祖细胞。 在胚胎发育过程中的种群。肾单位祖细胞(NPC)自我更新和分化的微妙平衡 在肾脏过程中，需要分化以产生与物种相适应的数量的肾单位。 发展。转录调控因子SIX2与Wnt/β-连环蛋白信号的转录调节因子 途径，LEF/Tcf因子，在平衡NPC的维持和承诺方面发挥着关键作用。在这里，SIX2是 对鼻咽癌的自我更新至关重要，并与LEF/Tcf因子相互作用。β-连环蛋白的积累起到了密码转换的作用 LEF/Tcf因子参与的分化靶标从抑制子到激活子转录信号。这个 在这一建议中检验的首要假设是β-连环蛋白的积累切换了LEF/Tcf调节 签名从关闭状态变为打开状态。在目标1中，我将进行功能丧失实验来解开机制 依赖于β-连环蛋白浓度的Tcf/Lef因子参与导致转录变化的作用。 在AIM 2中，我将进行多蛋白质蛋白质组分析，以确定β-连环蛋白周围的多蛋白质复合体 免疫沉淀和基于质谱学的亲和蛋白质组学机制研究 Wnt/β-catenin信号与已确定的结合伙伴结合将促进肾单位样细胞的产生 肾脏疾病的体外和最终再生疗法的类型。

PROJECT ABSTRACT Approximately 4.9 million adults in the US suffer from kidney disease. Current therapies do not provide curative treatments for end state renal disease. Regenerative nephrology holds promise for developing novel therapeutic strategies. The functional unit of the kidney is the nephron, which is derived from a distinct progenitor cell population during embryonic development. A delicate balance of nephron progenitor cell (NPC) self-renewal and differentiation is required to generate a species-appropriate number of nephrons during the course of kidney development. The transcriptional regulator Six2, and transcriptional mediators of the Wnt/β-catenin signaling pathway, Lef/Tcf factors, play critical roles balancing the maintenance and commitment of NPCs. In this, Six2 is essential for NPC self-renewal and interacts with Lef/Tcf factors. β-catenin accumulation acts to switch the code of Lef/Tcf factor engagement at differentiation targets from a repressor to activator transcriptional signature. The overarching hypothesis tested in this proposal is that β-catenin accumulation switches the Lef/Tcf regulatory signature from an OFF to ON state. In AIM 1, I will perform loss of function experiments to unravel the mechanism of action of β-catenin concentration dependent Tcf/Lef factor engagement resulting in transcriptional changes. In AIM 2, I will perform multi-protein proteomic analysis to define multiprotein complexes surrounding β-catenin with immunoprecipitation and mass spectrometry-based affinity proteomics Mechanistic understanding of Wnt/β-catenin signaling in concert with identified binding partners will facilitate the derivation of nephron-like cell types in vitro and ultimately regenerative therapies for renal diseases.