Translation control of stress response and innate immunity

应激反应和先天免疫的翻译控制

• 批准号: 10004111
• 负责人: HYUNG D RYOO
• 金额: $ 34.08万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-20 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10004111
• 关键词: 5' Untranslated Regions; ATF6 gene; Affect; Animal Model; Animals; Attenuated; Bacterial Infections; Cells; Cellular Stress; Cellular Stress Response; Development; Diabetes Mellitus; Disease; Drosophila genus; EIF4EBP1 gene; Endoplasmic Reticulum; Gene Expression; Gene Expression Regulation; Genetic Transcription; Genetic Translation; Goals; Health; Human; Impairment; Inflammation; Innate Immune Response; Internal Ribosome Entry Site; Longevity; Mammals; Mediating; Messenger RNA; Metabolic Diseases; Molecular Genetics; Natural Immunity; Neurodegenerative Disorders; Nutrient; Open Reading Frames; Pathogenicity; Pathologic; Pathway interactions; Peptide Initiation Factors; Phenotype; Phosphorylation; Phosphotransferases; Physiological; RNA interference screen; Regulation; Resistance; Stress; Stress Response Signaling; Structure; Structure of beta Cell of islet; Study models; Testing; Therapeutic; Time; Transcript; Translational Regulation; Translational Repression; Translations; antimicrobial peptide; attenuation; base; biological adaptation to stress; endoplasmic reticulum stress; experimental study; genomic tools; inhibitor/antagonist; insight; interest; mutant; novel; prevent; programs; response; ribosome profiling; transcription factor

Project Summary The long-term goal of this project is to understand how mRNA translational regulatory mechanisms control cellular stress response under physiological and pathological conditions. The specific pathway of interest is the Integrated Stress Response (ISR), which involves stress-responsive kinases that phosphorylate the α subunit of eIF2 to attenuate general translational initiation. More recently, we discovered that ISR inhibits mRNA translation through the induction of yet another translational inhibitor 4E-BP. At the same time, such conditions paradoxically stimulate the translation of transcription factors such as ATF4, due to the presence of regulatory upstream Open Reading Frames (uORFs) that precede the main ATF4 ORF. How stress responsive transcripts evade translational inhibition, or even undergo more active expression, in stressed cells is one of the major conceptual questions that remains poorly understood. Our preliminary studies using Drosophila have led us to a number of new insights to this question: These include our findings that (1) ISR boosts innate immune response to bacterial infection and anti-microbial peptides have 5’UTRs that can evade translational inhibition imposed by ISR signaling, (2) that previously unexpected factors regulate the activation of ISR, and (3) that ATF6 also has a 5’UTR that stimulates the main ORF translation in response to stress. Here I propose to use Drosophila to investigate the underlying regulatory mechanisms and determine how the newly identified ISR regulatory factors affect innate immune response, inflammation, and lifespan of Drosophila. We will supplement the molecular genetics-based approach with genomic tools such as ribosome profiling and structure-based modeling studies. Three Specific Aims will be pursued: (1) We will determine how ISR signaling enhances innate immune response, mainly focusing on the idea that anti-microbial peptide transcripts undergo mRNA translation through an unconventional mechanism to evade translational inhibition associated with ISR signaling. (2) Through the characterization of the novel ISR regulators that we have identified, we plan to determine how uORF containing transcripts increase their translation when general mRNA translation is suppressed, and examine how they affect phenotypes associated with abnormal ISR regulation. (3) We will test the hypothesis that ATF6 is another transcription factor that is regulated at the level of mRNA translation during ISR to mediate its transcriptional response. Notably, impairment or excessive stimulation of this pathway underlies various neurodegenerative and metabolic disorders in humans. Therefore, a better understanding of the regulatory mechanisms will not only advance our conceptual understanding of gene expression regulation in cells under stress but also may prompt the development of new strategies to modulate ISR signaling for therapeutic purposes.

项目摘要 该项目的长期目标是了解mRNA如何翻译监管机制 在身体和病理条件下的细胞应力反应。感兴趣的具体途径是 综合应力反应（ISR），涉及磷酸化的应力响应激酶，使α亚基的α亚基磷酸化 EIF2减弱一般翻译计划。最近，我们发现ISR抑制mRNA翻译 通过诱导另一种翻译抑制剂4E-BP。同时，这种情况 由于存在调节，因此矛盾地刺激转录因子（例如ATF4）的翻译 在主要ATF4 ORF之前的上游打开读帧（UORF）。压力响应式成绩单如何 逃避翻译抑制，甚至在压力细胞中进行更活跃的表达是主要的 概念性问题仍然很糟糕。我们使用果蝇的初步研究使我们达到了 这个问题的新见解数量：其中包括我们的发现（1）ISR Bowos先天免疫反应 细菌感染和抗微生物辣椒具有5'Utrs，可以逃避由 ISR信号传导，（2）以前出乎意料的因素调节ISR的激活，（3）ATF6也具有A 5'Utr刺激主要的ORF翻译，以应对压力。在这里，我建议使用果蝇 研究潜在的调节机制，并确定新鉴定的ISR调节因素如何 影响果蝇的先天免疫反应，炎症和寿命。我们将补充分子 基于遗传学的方法，具有基因组工具，例如核糖体分析和基于结构的建模研究。 将追求三个具体目标：（1）我们将确定ISR信号如何增强先天免疫 反应主要关注抗微生物肽转录本通过 逃避与ISR信号相关的转化抑制的非常规机制。 （2）通过 我们已经确定的新型ISR调节剂的表征，我们计划确定含有UORF的方式 当抑制一般mRNA翻译时，成绩单会增加其翻译，并检查它们如何 影响与异常ISR调节相关的表型。 （3）我们将检验以下假设：ATF6是另一种 在ISR期间在mRNA翻译水平上调节的转录因子以介导其转录 回复。值得注意的是，这种途径的损害或过量刺激是各种神经退行性的基础 和人类的代谢障碍。因此，对监管机制的更好理解不仅将 促进我们对压力下细胞中基因表达调节调节的概念理解，但也可能促使 为治疗目的调节ISR信号的新策略的制定。