Screening for modifiers of PKD severity using ENU Mutagenesis

摘要 从对人类种群和老鼠模型的分析中有大量证据表明， 多囊肾病(PKD)可以通过相互作用的遗传位点进行修饰。这些基因座的鉴定 应该有助于我们对囊性发生和疾病的基本病理生物学的理解 进步。重要的是，它们可能揭示治疗干预的新途径。我们有 在囊性肾脏病小鼠模型的表征方面有丰富的经验，特别是 对其严重程度的菌株特异性修饰物的研究。然而，在小鼠中已证实的因果基因的产量 这种类型的研究一直很少。相比之下，我们已经非常成功地使用了不同的方法 新的疾病基因发现，即用化学物质乙基亚硝脲(ENU)进行诱变。我们有 最近修改了这种方法，这样我们就可以完全在近亲繁殖的背景下显示屏幕，使用 用于位置克隆的基因组测序方法。PKD1RC突变体的最新特征 由于小鼠具有缓慢进展的PKD，对菌株特定的修饰物敏感，迫使我们提出建议 我们利用ENU诱变产生和发现PKD_1诱导的囊性肾的修饰物 疾病。为了补充这种表型驱动的方法，我们还将对候选基因座进行分析， 可能会修改PKD的严重性。我们有数据表明Sonic Hedgehog(SHH)信号在 我们将测试这一途径中的基因缺失是否会影响疾病的严重性 PKD1RC小鼠模型。

ABSTRACT There is abundant evidence from the analysis of human populations and mouse models that the severity of Polycystic Kidney Disease (PKD) can be modified by interacting genetic loci. The identification of these loci should provide insight into our understanding of the basic pathobiology of cystogenesis and disease progression. Importantly, they can potentially reveal novel pathways of therapeutic intervention. We have extensive experience in the characterization of a mouse model of cystic kidney disease, and specifically the investigation of strain-specific modifiers of its severity. However, the yield of proven causal genes in mouse studies of this type has been low. In contrast, we have been very successful using a different approach for novel disease gene discovery, namely mutagenesis with the chemical ethyl-nitrosourea (ENU). We have recently modified this method so that we can do our screen entirely on an inbred background, using Whole Genome Sequencing methodology for positional cloning. The recent characterization of the PKD1RC mutant mouse as having slowly progressive PKD, which is sensitive to strain-specific modifiers, compels our proposal that we use ENU mutagenesis for the generation and discovery of modifiers of PKD1-induced cystic kidney disease. To complement this phenotype-driven approach, we will also pursue an analysis of candidate loci that may modify PKD severity. We have data to suggest that Sonic Hedgehog (SHH) signaling plays a role in cystogenesis, and we will test whether the deletion of genes in this pathway affects disease severity in the PKD1RC mouse model.