Investigating Biomolecular Condensates and Heat Shock Proteins in Cellular Responses to Sublethal Heat Shock and Fever

研究细胞对亚致死热休克和发烧反应中的生物分子缩合物和热休克蛋白

• 批准号: 10679768
• 负责人: Kyle Matthew Lin
• 金额: $ 5.27万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10679768
• 关键词: Affect; Affinity; Animals; Area; Behavior; Binding; Biochemical; Biological Models; Biology; Cell Line; Cells; Cellular biology; Cessation of life; Circadian Rhythms; Collaborations; Complement; Cyanobacterium; Disease; Environment; Eukaryota; Event; Fever; Generations; Genetic Transcription; Growth; Health; Heat Stroke; Heat shock proteins; Heat-Shock Response; Homeostasis; Human; Human Biology; Human Cell Line; Hyperthermia; Immune; Immune system; Infection; Inflammatory Response; Investigation; Ion Channel; Knowledge; Life; Mammalian Cell; Mass Spectrum Analysis; Methods; Microscopic; Microscopy; Molecular; Molecular Chaperones; Physical condensation; Physiological; Physiology; Positioning Attribute; Proteins; RNA; Repression; Sedimentation process; Stimulus; Stress; Temperature; Testing; Tissues; Titrations; Translating; Work; Yeasts; cell type; climate change; exhaustion; experience; extreme heat; feeding; migration; misfolded protein; molecular scale; mortality; protein aggregation; protein expression; protein folding; response; sensor; sex determination; single molecule; stem; trafficking; transcription factor; transcriptome sequencing; warm temperature

Project Summary Environmental temperature dictates biology. Animals use their thermal environments to guide their migration, circadian rhythms, growth, feeding, and sex determination: essential behaviors now threatened by changing climates. Warming temperatures likewise challenge human health. About 1 in 100 deaths globally stem from heat-related causes, and such mortality is rising. Beyond lethal heatstroke, more mild heat affects human health in far more common and pervasive ways. Heat <40°C alters and dysregulates human physiology down to the cellular level, particularly in immune cells. Such sublethal heat shocks occur in hyperthermia and heat illness, as well as frequently in fever: a systemic heat shock which regulates the immune system during infection. Yet even in the well-known context of fever, we lack understanding of how human cells sense sublethal heat shock. The cell biology of extreme heat shock >40°C is well-characterized, but far less is understood about sublethal, fever-range temperatures <40°C. However, we do know that certain immune cells upregulate heat shock protein expression in response to fever. The induction of heat shock proteins, or the heat shock response, occurs in eukaryotes when heat activates transcription factor Hsf1, via titration of its repressor (heat shock protein Hsp70) away from Hsf1. This titration is caused by the generation of new, heat shock-induced substrates for Hsp70 to bind. These substrates, i.e. the upstream sensors of heat, are unidentified in sublethal heat shock. We hypothesize biomolecular condensates are these substrates which help cells sense sublethal heat shock. Condensation, or reorganization of proteins and RNA into larger foci, occurs in response to environmental stimuli across species from yeast to humans. Our group showed recently that heat-induced condensates are Hsp70 substrates in yeast. We hypothesize that sublethal heat shock-induced condensates are Hsp70 substrates in humans, enabling cells to sense and respond to such fever-range temperatures. It is not known what proteins condense in human cells at these temperatures, nor if such condensates might be Hsp70 substrates. Moreover, in any species, we lack molecular-scale understanding of how condensates and Hsp70 interact. We are poised to unlock exactly this knowledge using a complement of biochemical, microscopic, and molecular-level approaches. First, we will uncover protein condensation in human cell lines at fever-range temperature, using the established sedimentation-mass spectrometry method of our group. Second, we will observe directly how condensates and Hsp70 interact at the molecular scale, using single-molecule microscopy. Together, these aims will help us elucidate fundamentally how cells sense and respond to sublethal heat shock.

项目摘要 环境温度决定生物学。动物使用热环境来指导他们 迁移，昼夜节律，成长，喂养和性别确定：现在受到威胁的基本行为 气候。温暖的温度同样挑战人类健康。全球100人中大约有1个死亡人数 与热有关的原因，这种死亡率正在上升。除了致命的热演之外，更多的温和热会影响人类 以更加普遍和普遍的方式健康。热量<40°C改变并使人类生理失调至 细胞水平，特别是在免疫细胞中。这种一定的热冲击发生在高温和热病中， 以及频繁的发烧：一种全身热冲击，可调节感染过程中的免疫系统。然而 即使在众所周知的发烧背景下，我们也缺乏对人类细胞如何感应热量冲击的理解。 极热冲击> 40°C的细胞生物学特征良好，但对 余生，发烧范围<40°C。但是，我们确实知道某些免疫细胞上调了热量 响应发烧的休克蛋白表达。热激蛋白的诱导或热激响应， 当热量通过滴定其反射器（热激蛋白）激活转录因子HSF1时，发生在真核生物中 HSP70）远离HSF1。这种滴定是由新的，热冲击引起的底物产生的 HSP70结合。这些底物，即热的上游传感器，在全部热量冲击中是未鉴定的。 我们假设生物分子冷凝物是这些底物，这些底物有助于细胞感知脱脂热 震惊。蛋白质和RNA凝结或重组为较大的焦点，是为了响应环境而发生的 从酵母到人类的跨物种刺激。我们的小组最近表明热诱导的冷凝水是 酵母中的HSP70底物。我们假设一定的热休克引起的冷凝水为HSP70 人类的底物使细胞能够感知并响应这种发烧范围的温度。这是不知道的 在这些温度下，哪些蛋白质在人类细胞中的凝结，或者是否可能是HSP70的蛋白质 基材。此外，在任何物种中，我们都缺乏对冷凝水和HSP70的理解 相互影响。我们被毒死了，以完成生化，微观和微观和 分子级方法。首先，我们将在发烧范围内发现人类细胞系中的蛋白质凝结 温度，使用我们组已建立的沉积物质谱法。第二，我们会的 直接使用单分子显微镜直接观察凝结物和HSP70如何在分子尺度上相互作用。 这些目标共同阐明了细胞如何感知和对全脂冲击的反应。