Regulation of Kidney-Specific Gene Expression

肾脏特异性基因表达的调控

• 批准号: 10743246
• 负责人: Peter Igarashi
• 金额: $ 30.99万
• 依托单位: STATE UNIVERSITY NEW YORK STONY BROOK
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-11-18 至 2026-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10743246
• 关键词: Regulation; Kidney; Specific; Gene; Expression

ABSTRACT The purpose of this MERIT renewal is to continue our studies on hepatocyte nuclear factor-1β (HNF-1β) and its roles in kidney-specific gene expression and cystic kidney diseases. HNF-1β is a DNA-binding transcription factor that regulates tissue-specific gene expression in the kidney and other epithelial organs. Mutations of HNF- 1β produce congenital anomalies of the kidney and urinary tract, cystic kidney disease, autosomal dominant tubulointerstitial kidney disease, and inherited tubulopathies. To unravel the pathogenesis of these disorders, we have produced HNF-1β mutant mice that develop phenotypes similar to those seen in affected humans. Analysis of the mutant mice has revealed that HNF-1β plays a central role in the expression of polycystic kidney disease genes, such as PKD2 and PKHD1. During the last project period, we used genome-wide ChIP-seq and RNA-seq to identify transcriptional networks that are directly regulated by HNF-1β. Together with new mutant mouse models, these studies uncovered novel roles of HNF-1β in the regulation of Wnt signaling, cAMP signaling, lipid metabolism, urinary concentration, and expression of noncoding RNAs. Preliminary studies using mass spectrometry revealed that HNF-1β interacts with proteins involved in chromatin remodeling, histone modification, and transcription elongation. In the next project period we will extend this work to further unravel the functions of HNF-1β in the kidney. Specific Aim 1 will use biochemical studies to unravel the molecular mechanisms whereby HNF-1β represses Wnt pathway genes. We will test the hypothesis that HNF-1β forms repressive chromatin loops that exert long-range effects on histone modification, chromatin remodeling, and transcription elongation. Specific Aim 2 will apply mouse genetics to elucidate the roles of dysregulated Wnt signaling in the HNF-1β mutant phenotype. We will determine whether mutations of Wnt pathway genes that are overexpressed in HNF-1β mutant mice improve kidney function and structure. Collectively, the proposed studies will advance our understanding of gene regulation, unravel how mutations of HNF-1β produce kidney abnormalities, and identify potential therapeutic targets for HNF-1β-related cystic kidney diseases.

抽象的 本次MERIT更新的目的是继续我们对肝细胞核因子-1β（HNF-1β）及其相关的研究 在肾脏特异性基因表达和囊性肾病中的作用。 HNF-1β 是一种 DNA 结合转录 调节肾脏和其他上皮器官中组织特异性基因表达的因子。 HNF-的突变 1β 产生肾脏和泌尿道先天性异常、囊性肾病、常染色体显性遗传 肾小管间质性肾病和遗传性肾小管病。为了阐明这些疾病的发病机制， 我们已经培育出 HNF-1β 突变小鼠，其表型与受影响的人类相似。 对突变小鼠的分析表明，HNF-1β在多囊肾的表达中起着核心作用 疾病基因，例如 PKD2 和 PKHD1。在上一个项目期间，我们使用了全基因组 ChIP-seq 和 RNA-seq 用于识别受 HNF-1β 直接调控的转录网络。与新变种人一起 小鼠模型中，这些研究揭示了 HNF-1β 在 Wnt 信号传导、cAMP 调节中的新作用 信号传导、脂质代谢、尿浓度和非编码 RNA 的表达。初步研究使用 质谱分析显示 HNF-1β 与参与染色质重塑的蛋白质、组蛋白相互作用 修饰和转录延伸。在下一个项目期间，我们将扩展这项工作以进一步阐明 HNF-1β 在肾脏中的功能。具体目标 1 将利用生化研究来解开分子 HNF-1β 抑制 Wnt 通路基因的机制。我们将检验 HNF-1β 形成的假设 抑制性染色质环对组蛋白修饰、染色质重塑和 转录延伸。具体目标 2 将应用小鼠遗传学来阐明 Wnt 失调的作用 HNF-1β 突变表型中的信号传导。我们将确定 Wnt 通路基因的突变是否 在 HNF-1β 突变小鼠中过度表达可改善肾功能和结构。总的来说，拟议的研究 将增进我们对基因调控的理解，揭示 HNF-1β 突变如何产生肾脏 异常，并确定 HNF-1β 相关囊性肾病的潜在治疗靶点。