Role of autophagy and other downstream effectors in lifespan extension by teh GCN4/ATF4 pahtway

自噬和其他下游效应子在 GCN4/ATF4 途径延长寿命中的作用

• 批准号: 10248579
• 负责人: Mark McCormick
• 金额: $ 27.74万
• 依托单位: UNIVERSITY OF NEW MEXICO HEALTH SCIS CTR
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-05-14 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10248579
• 关键词: Age; Aging; Alzheimer' s Disease; Analysis of Variance; Animal Model; Animals; Autophagocytosis; Caloric Restriction; Data; Dependence; Disease; Distant; Drug Targeting; Genetic Transcription; Goals; Human Biology; IGF1 gene; Inflammation; Insulin; Intervention; Light; Longevity; Malignant Neoplasms; Measurement; Measures; Mediating; Metabolism; Mitochondria; Modeling; Output; Pathway interactions; Phenotype; Play; Prevention; Prevention approach; Proteins; Research; Role; Signal Transduction; Testing; Transcript; Validation; Yeasts; activating transcription factor; design; experimental study; human disease; innovation; novel; protein degradation; transcription factor; transcriptome sequencing

We now know multiple pathways that delay aging, and have extended the lifespan of some animals by as much as 10-fold, yet we do not fully understand the final mechanistic effectors of delayed aging in any example to date. Thus we do not know the underlying changes involved in natural aging, presumably offset or delayed by our interventions. The long-term goal is to is to understand the most downstream changes in delayed aging. This will allow a rational approach to developing interventions to broadly delay the onset of multiple human diseases of aging such as Alzheimer’s disease and cancer. The overall objective in this application, the next step in pursuit of that long-term goal, is to understand downstream effectors of delayed aging specifically in the novel Gcn4 pathway. The central hypothesis is that targets of conserved transcription factor Gcn4 are the likely effectors, that the most relevant of these will be shared by multiple distinct Gcn4-dependent interventions, and that autophagy and increased protein turnover are likely to play a key role. The rationale for the proposed research is two-fold: 1) once we know the effectors of Gcn4-mediated delayed aging, they can be directly manipulated, giving approaches for prevention and treatment of human diseases of aging; 2) A functionally validated set of effectors allows us to ask if these are shared by other pathways, and will also shed light on the changes that underly natural aging. Guided by our preliminary data, this will be tested by pursuing three specific aims: 1) Determine the Gcn4-dependence of mitochondrial translational deletions; 2) Determine the role of autophagy in Gcn4-mediated delayed aging; and 3) Identify and validate the most functionally relevant transcriptional targets of Gcn4 / ATF-5. In part of the second aim we will use the UNM AIM CoBRE Core Amnis Imagestream to simultaneously measure the age, autophagy level, and Gcn4 protein level of thousands of yeast. The approach is innovative, in the applicant’s opinion, because it represents a new and substantive departure from the status quo byassaying transcriptional output following multiple distinct interventions dependent on the same transcription factor, using a novel block design RNAseq-ANOVA model of changes in transcript levels, in order to focus specifically on those transcriptional changes tied to our phenotype of delayed aging while excluding others. It also uses validation through lifespan measurements experiments in two distantly related model organisms, to ask which changes are most conserved, and thus most likely to be relevant to human biology. The proposed research is significant, because a fuller understanding of the downstream effectors of delayed aging will identify drug targets with translational importance in the prevention and treatment of multiple human diseases of aging. The potential impact of these findings is underscored by the fact that we cannot now preclude the possibility that multiple known pathways that delay aging, such as caloric restriction, Insulin / IGF1 signaling, and TOR, all effect their phenotype largely through changes in autophagy, nor can we rule out that all of these pathways do this in some part by converging on Gcn4.

我们现在知道了多种延缓衰老的途径，并且已经将一些动物的寿命延长了10年。 多达10倍，但我们并没有完全了解任何例子中延迟衰老的最终机制效应 迄今因此，我们不知道自然衰老的潜在变化，可能是抵消或延迟 通过我们的干预。长期目标是了解延迟衰老的最下游变化。 这将允许采取合理的方法来制定干预措施，以广泛延迟多个人的发病。 老年性疾病，如阿尔茨海默病和癌症。本申请的总体目标是， 追求长期目标步骤是了解延迟衰老的下游效应物，特别是在 新的Gcn 4通路。核心假设是保守的转录因子Gcn 4的靶点可能是 效应子，其中最相关的将由多种不同的Gcn 4依赖性干预措施共享，以及 自噬和蛋白质周转的增加可能起着关键作用。建议的理由 研究是双重的：1）一旦我们知道Gcn 4介导的延迟衰老的效应器，它们可以直接 操作，为预防和治疗人类衰老疾病提供方法; 2）功能上 一组经过验证的效应子使我们能够询问这些效应子是否被其他通路共享，并且还将阐明 自然衰老的变化。根据我们的初步数据，这将通过追踪三个 具体目的：1）确定线粒体翻译缺失的Gcn 4依赖性; 2）确定线粒体翻译缺失的Gcn 4依赖性。 自噬在Gcn 4介导的延迟衰老中的作用;以及3）识别和验证功能上最相关的 Gcn 4/ ATF-5的转录靶点。在第二个目标的一部分，我们将使用UNM AIM CobRE Core Amnis 同时测量数千名受试者的年龄、自噬水平和Gcn 4蛋白水平。 酵母申请人认为，这一办法具有创新性，因为它代表了一种新的实质性的 通过测定多种不同干预后的转录输出， 依赖于相同的转录因子，使用一种新的区组设计RNAseq-ANOVA模型， 转录水平，以便特别关注与我们的延迟表型相关的转录变化。 而排斥他人。它还通过两个寿命测量实验进行验证 远亲模式生物，问哪些变化是最保守的，因此最有可能是 与人类生物学有关。拟议的研究是重要的，因为更全面地了解 延迟衰老的下游效应物将确定在预防中具有转化重要性的药物靶点 和治疗多种人类衰老疾病。这些研究结果的潜在影响是强调， 事实上，我们现在不能排除多种已知的延缓衰老的途径，如 热量限制、胰岛素/IGF 1信号传导和TOR都主要通过改变 自噬，我们也不能排除所有这些途径都在某种程度上通过聚集在Gcn 4上来实现这一点。