Drosophila as a model to study modifiers of Cystic Fibrosis

果蝇作为研究囊性纤维化修饰因子的模型

• 批准号: 10386551
• 负责人: Elizabeth Lane
• 金额: $ 6.64万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-03-03 至 2025-03-02
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10386551
• 关键词: Drosophila; model; study; modifiers; Cystic

Summary/abstract Cystic Fibrosis (CF) is genetic disorder that effects approximately 30,000 people in the United states and more then 70,000 worldwide. CF is caused by mutations in the epithelial chloride channel CF transmembrane conductance regulator (CFTR) gene. In CF, loss-of-function mutations in CFTR, reduces chloride efflux from cells, and elevates the activity of the epithelial sodium channel (ENaC) through a mechanism that is not fully understood. This results in an increase sodium and water reabsorption, which ultimately leads to dehydration of the epithelial surface and reduction in mucus transport in multiple mucin-producing organs, such as the lungs, sinuses, intestine, pancreas, and reproductive organs. CF patients develop clinical symptoms in all these mucus- producing organs. In particular, most CF patients have shortened lifespans because of loss of CFTR in the respiratory tract, but also develop gut phenotypes early in the progression of the disease. These gut phenotypes are less studied than the lung phenotypes of CF but still significantly impact CF patients lives. While CF is caused by many different mutations in CFTR, the differences in CFTR function cannot explain the differences in patient symptoms. This indicates that many of the clinical phenotypes of CF are influenced by genetic modifiers and/or environmental factors. These genetic modifiers and environmental factors could be additional targets to develop treatments for CF that could be used to treat all patients regardless of the mutation they harbor. However, many of the potential genetic modifiers of CF are not well studied and the mechanism by which they modify CF phenotypes is unknown. Our lab has recently identified a Drosophila ortholog of the CFTR gene and established a CF model in the fly gut epithelium. In addition to observing CF phenotypes in the gut epithelium of CFTR mutant flies, we uncovered a micro RNA, mir263a, as a negative regulator of ENaC activity. Interestingly, the expression of mir263a is decreased in CFTR mutant flies, suggesting that that the regulation of ENAC by CFTR is regulated in part by mir263a. Here, I propose to further characterize the pathology of the fly mutant model including examining how bacteria can modulate disease phenotypes in this model. I will then use the fly CF model to gain new insight into ENaC, a known modifier of the CF phenotype. Finally, as the short lifespan, low cost, and genetic tractability of the fly makes it an ideal model organism to perform genetic screens, I propose to identify new potential genetic modifiers of CF. Altogether this work will establish Drosophila as a useful model to study CF and potentially provide new molecular targets for treatment of the disease.

摘要/摘要 囊性纤维化是一种遗传性疾病，在美国大约有30,000人或更多人受到影响 然后在全球范围内达到7万。Cf是由上皮氯通道Cf跨膜突变引起的 电导调节因子(CFTR)基因。在CF中，CFTR功能丧失突变，减少氯离子外流 并通过一种不完全的机制提高上皮钠通道(ENaC)的活性 明白了。这会导致钠和水的重吸收增加，最终导致脱水 在多个产生粘蛋白的器官，如肺，上皮表面和粘液运输的减少， 鼻窦、肠道、胰腺和生殖器官。Cf患者在所有这些粘液中出现临床症状- 产生器官。特别是，大多数CF患者的寿命都缩短了，这是因为在 呼吸道，但也会在疾病进展的早期形成肠道表型。这些肠道表型 与CF的肺表型相比研究较少，但仍对CF患者的生活有显著影响。而引起慢性阻塞性肺疾病 由于cftr有许多不同的突变，cftr功能的差异不能解释患者之间的差异 症状。这表明许多CF的临床表型受到遗传修饰物和/或 环境因素。这些遗传修饰物和环境因素可能成为开发的额外目标。 可用于治疗所有患者的CF治疗方法，无论他们携带的突变是什么。然而，许多人 其中潜在的遗传修饰剂尚未得到很好的研究，以及它们对纤维的修饰机理 表型尚不清楚。 我们的实验室最近发现了一个果蝇CFTR基因的直系同源基因，并在 苍蝇肠道上皮。除了观察cftr突变果蝇肠道上皮中的cf表型外，我们还 发现了一个微小的RNA，mir263a，作为ENaC活性的负调节因子。有趣的是， 在cftr突变果蝇中，mir263a的表达减少，这表明cftr对ENAC的调控是受调控的 部分是由米尔263a造成的。在这里，我建议进一步描述苍蝇突变模型的病理学特征，包括 在这个模型中，研究细菌如何调节疾病表型。然后我将使用Fly CF模型来获得 对ENaC的新见解，ENaC是一种已知的CF表型修饰物。最后，由于寿命短，成本低，而且基因 苍蝇的可驯性使它成为进行遗传筛选的理想模式生物，我建议识别新的 潜在的遗传修饰因子。总之，这项工作将建立果蝇作为研究CF的有用模型 并有可能为该病的治疗提供新的分子靶点。