Genetic and Genomic Analysis of Starvation Resistance in C. elegans

项目摘要 通过控制生长和静止，营养反应途径是癌症，糖尿病和衰老的核心。 这些途径在饥饿中的功能使人们了解了它们在疾病中的功能障碍，但它们在饥饿中的作用是不一样的。 在饥饿中的重要作用还没有得到很好的理解。这一建议的前提是，多个肿瘤超- 已知升压因子可促进饥饿抵抗力，但它们的调节关系和效应机制， nisms不清楚。该项目的长期目标是阐明遗传基础和分子 C.作为人类疾病的模型。蠕虫是一个理想的模型 因为他们在盛宴和饥荒中茁壮成长，具有非凡的忍受饥饿的能力。已知基因促进 C. elegans（例如，daf-18/PTEN、daf-16/FoxO、lin-35/Rb、hlh-30/TFEB和aak-2/AMPK） 具有抑制肿瘤、调节代谢、延年益寿的保守功能。然而，在这方面， 在理解方面仍然存在重大差距。初步研究表明，抑制PI 3 K信号传导并不 解释了PTEN-18/PTEN对饥饿抗性的影响。他们显示，PTEN-18/PTEN蛋白- 磷酸酶活性促进饥饿抗性，他们确定了一个新的蛋白质靶点。初步重新- 结果还表明，β-16/FoxO和LIN-35/Rb调节组蛋白变异体介导的营养控制， 染色质结构和基因调控。他们也证明了创新人口的有效性- 测序方法用于分析数量性状，他们确定了影响自然变异的新基因 在饥饿抵抗力。这些包括胰岛素/IGF信号传导的修饰剂和保守但未表征的 转录因子这一提议的中心假设是，一个保守的肿瘤抑制因子网络 原癌基因通过多种效应机制控制饥饿抗性。的目标 这个建议是通过识别新的组件，调节相互作用， 和效应器机制。中心假设得到了强有力的初步数据和文献的支持- 是的。它将以以下三个目标进行测试：1）确定促进饥饿的β-18/PTEN靶点 2）确定调节饥饿适应的基因调节机制，3）确定基因 以及导致饥饿抗性自然变异的机制。遗传、基因组和生物化学 将采用各种方法来实现这些目标。这项工作在技术上是创新的使用人口se- 测序，以利用深度测序的力量进行统计遗传学，并利用基因表达作为 用于上位性分析高维性状。这是智力创新的假设一个新的监管 临床上重要的肿瘤抑制因子之间的关系。拟议工作的贡献将是 鉴定新的组分，调节网络的调节相互作用和效应机制 控制饥饿抵抗力。这些贡献将是重要的，因为饥饿抵抗是一个有趣的- 与人类健康和疾病密切相关的重要性状，并且所研究的基因是保守的。

PROJECT SUMMARY By governing growth and quiescence, nutrient-responsive pathways are central to cancer, diabetes and aging. The function of these pathways in starvation informs understanding of their dysfunction in disease, but their fundamental role in starvation is not well understood. The premise of this proposal is that multiple tumor sup- pressors are known to promote starvation resistance, but their regulatory relationships and effector mecha- nisms are unclear. The long-term goal of this project is to elucidate the genetic foundation and molecular mechanisms of starvation resistance in C. elegans as a model for human disease. Worms are an ideal model since they thrive in feast and famine with remarkable ability to endure starvation. Genes known to promote starvation resistance in C. elegans (eg, daf-18/PTEN, daf-16/FoxO, lin-35/Rb, hlh-30/TFEB and aak-2/AMPK) have conserved function in suppressing tumors, regulating metabolism, and promoting longevity. However, significant gaps in understanding remain. Preliminary studies show that inhibition of PI3K signaling does not account for the effect of DAF-18/PTEN on starvation resistance. They show that DAF-18/PTEN's protein- phosphatase activity promotes starvation resistance, and they identify a novel protein target. Preliminary re- sults also suggest that DAF-16/FoxO and LIN-35/Rb regulate histone variants to mediate nutritional control of chromatin structure and gene regulation. They also demonstrate the efficacy of an innovative population- sequencing approach for analysis of quantitative traits, and they identify novel genes affecting natural variation in starvation resistance. These include modifiers of insulin/IGF signaling and a conserved but uncharacterized transcription factor. The central hypothesis of this proposal is that a conserved network of tumor suppressors and proto-oncogenes governs starvation resistance through a variety of effector mechanisms. The objective of this proposal is to expand understanding of this network by identifying novel components, regulatory interac- tions, and effector mechanisms. The central hypothesis is supported by strong preliminary data and the litera- ture. It will be tested with the following three aims: 1) Identify DAF-18/PTEN targets that promote starvation resistance, 2) Identify gene regulatory mechanisms that mediate adaptation to starvation, and 3) Identify genes and mechanisms that contribute to natural variation in starvation resistance. Genetic, genomic and biochemical approaches will be used to complete these aims. This work is technically innovative for using population se- quencing to leverage the power of deep sequencing for statistical genetics, and for using gene expression as a high-dimensional trait for epistasis analysis. It is intellectually innovative for hypothesizing a novel regulatory relationship between clinically important tumor suppressors. The contributions of the proposed work will be identification of novel components, regulatory interactions and effector mechanisms of the regulatory network governing starvation resistance. These contributions will be significant because starvation resistance is a fun- damental trait intimately related to human health and disease, and genes under investigation are conserved.