Modulating Stochastic Gene Expression for Cell-fate Control and Therapeutics

调节随机基因表达以控制细胞命运和治疗

• 批准号: 10581483
• 负责人: Leor S Weinberger
• 金额: $ 91.84万
• 依托单位: J. DAVID GLADSTONE INSTITUTES
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-06-01 至 2026-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10581483
• 关键词: Address; Affect; Architecture; Attenuated; Award; Bacteria; Cell Fate Control; Cells; Cellular biology; Chemosensitization; Circadian Rhythms; Clinical; Cytoplasm; Data; Development; Disparate; Electrophysiology (science); Embryonic Development; Engineering; Enhancers; Evolution; FDA approved; Feedback; Flow Cytometry; Gene Expression; Genes; Genetic; Genetic Transcription; Goals; HIV; Heterogeneity; Intervention; Knowledge; Literature; Malignant Neoplasms; Mammalian Cell; Maps; Modeling; Molecular; Neurosciences; Noise; Nuclear Export; Outcome; Pathway interactions; Regulator Genes; Reporter; Research; Rest; Role; Safety; Science; Sensorimotor functions; Source; Specific qualifier value; Starvation; Stress; System; T-Lymphocyte; Testing; Therapeutic; Therapeutic Effect; Transcription Coactivator; Translations; Viral; Virus Diseases; Virus Latency; Work; Yeasts; biological systems; cell fate specification; circadian; clinical translation; drug repurposing; effective therapy; embryonic stem cell; improved; in vivo; knock-down; mathematical model; molecular modeling; mutant; novel; novel therapeutic intervention; pharmacologic; posttranscriptional; predictive modeling; reactivation from latency; stem cells; synergism; therapeutic development; therapeutic target; tool; transcriptome

PROJECT SUMMARY Stochastic fluctuations in gene expression are unavoidable at the single-cell level and affect fate decisions from HIV to embryonic development. Yet, there remain fundamental gaps in our understanding of the mechanisms generating and regulating expression fluctuations in mammalian cells. Addressing this gap in knowledge is critical to therapeutic development in systems where fluctuations and heterogeneity present treatment barriers, such as in HIV, stem-cell therapeutics, and cancer. Our long-term goal is to develop therapeutics that target mechanisms of cellular heterogeneity to overcome barriers to precise control of cell fate. During the past 5 years, our work established mechanistic roles for noise and heterogeneity, demonstrating that noise is a feature, rather than a bug, of biological systems that can be modulated for therapeutic effect. Specifically, we: (i) elucidated a viral transcriptional-feedback circuit that harnesses noise to regulate HIV latency, (ii) found this circuit to be optimized by evolution to function as a viral bet-hedging circuit, (iii) made contributions to cell biology showing that transcriptional fluctuations are, in general, amplified by nuclear export and translation, and, (iv) we discovered a novel post-transcriptional feedback architecture that efficiently suppresses noise to stabilize fate commitment. Most excitingly, and most relevant to this application, we (v) discovered noise- enhancer molecules that appear to substantially improve viral reactivation from latency and have been used by other labs to increase noise in diverse systems (e.g., circadian rhythm). The objective of this renewal is to identify molecular mechanisms of noise modulation in mammalian cell-fate circuits to enable therapeutic control of noise. Based on our findings and extensive preliminary evidence in embryonic stem cells (ESCs), our central hypothesis is that generalized `core' cellular mechanisms exist to tune expression noise and that these mechanisms can be pharmacologically perturbed. Our specific aims build off our unique tool of noise-enhancer molecules and will: (Aim 1) map the molecular mechanistic pathways of noise enhancer molecules to develop a mathematical model predictive of transcriptome-wide noise in mammalian cells; (Aim 2) map the molecular mechanisms of noise-suppressor molecules; and (Aim 3) to quantify relative contributions of stochastic vs. deterministic mechanisms underlying HIV latency in vivo and safety & efficacy of noise-modulating molecules in vivo. The proposed research has broad significance as it will determine core molecular mechanisms regulating expression in disparate fate-specification models, reveal genetic targets of noise enhancement and suppression that can lead to the development of new broad-spectrum noise modulators, and propel clinical translation of noise-modulating molecules. Ultimately, the knowledge gained will guide new therapeutic approaches to overcome barriers to precise cell-fate control across diverse mammalian systems.

项目摘要 基因表达中随机波动在单细胞水平上不可避免，并影响命运的决定 艾滋病毒致胚胎发育。然而，我们对机制的理解仍然存在根本的差距 在哺乳动物细胞中产生和调节表达波动。在知识上解决这一差距是 在波动和异质性目前的治疗障碍的系统中，对治疗发展至关重要， 例如在艾滋病毒中，干细胞疗法和癌症。我们的长期目标是开发针对目标的治疗剂 细胞异质性的机制克服了精确控制细胞命运的障碍。 在过去的5年中，我们的工作确立了噪声和异质性的机械作用，表明 噪声是可以调节治疗效果的生物系统的特征，而不是错误。 具体而言，我们：（i）阐明了一个病毒转录反馈电路，该反馈利用噪声来调节艾滋病毒潜伏期， （ii）发现该电路通过进化来优化，以充当病毒的围墙电路，（iii）做出了贡献 细胞生物学表明转录波动通常是通过核输出和翻译扩大的 （iv）我们发现了一种新颖的转录后反馈结构，可有效抑制噪声 稳定命运承诺。最令人兴奋的是，与此应用程序最相关，我们（v）发现了噪音 - 增强子分子似乎从潜伏期中大大改善了病毒重新激活，并且已被使用 由其他实验室增加了各种系统（例如昼夜节律）的噪声。 这种更新的目的是识别哺乳动物细胞触发中噪声调节的分子机制 电路可以对噪声进行治疗控制。根据我们的发现和广泛的初步证据 胚胎干细胞（ESC），我们的中心假设是存在广义的“核心”细胞机制 表达噪声，这些机制可以在药理上受到干扰。我们的具体目标是建立的 我们独特的噪声增强器分子工具，将：（AIM 1）绘制噪声的分子机械途径 增强子分子以开发哺乳动物中转录组噪声的数学模型 细胞； （AIM 2）绘制噪声抑制剂分子的分子机制； （目标3）量化相对 随机性与确定性机制的贡献，体内艾滋病毒潜伏期和安全性的贡献 体内噪声调节分子的功效。拟议的研究具有广泛的意义，因为它将决定 核心分子机制调节在不同命运规格模型中的表达，揭示了遗传靶标 增强噪音和抑制，可能导致新的广谱噪声的发展 调节剂和推动调节分子的临床翻译。最终，获得的知识将 指导新的治疗方法，以克服各种哺乳动物的精确细胞效果控制障碍 系统。