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

基本信息

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
项目类别：
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

项目摘要

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.

项目概要环境温度决定了动物的生物学行为。迁徙、昼夜节律、生长、进食和性别决定：基本行为现在受到威胁气候变化同样对人类健康构成挑战。全球约有百分之一的死亡是由气候变化引起的。由于与高温相关的原因，这种死亡率正在上升，除了致命的中暑之外，更温和的高温也会影响人类。低于 40°C 的高温会以更常见和普遍的方式改变人体生理学并使其失调。细胞水平，特别是在免疫细胞中，这种亚致死的热休克发生在高热和热病中，以及经常发烧：感染期间调节免疫系统的全身热休克。即使在众所周知的发烧背景下，我们也缺乏对人体细胞如何感知亚致死热休克的了解。 >40°C 的极端热休克的细胞生物学已被充分表征，但人们对其了解甚少亚致死、发烧范围温度<40°C 然而，我们确实知道某些免疫细胞会上调热量。响应发烧的休克蛋白表达热休克蛋白的诱导，或热休克反应，当热量通过滴定其阻遏物（热休克蛋白）激活转录因子 Hsf1 时，真核生物中就会发生这种情况 Hsp70) 远离 Hsf1，这种滴定是由新的、热激诱导的底物的生成引起的。这些底物，即热的上游传感器，在亚致死热休克中尚未被识别。我们捕获的生物分子凝聚物是这些帮助细胞感知亚致死热量的底物蛋白质和 RNA 凝结或重组为更大的焦点，是对环境的反应。我们的小组最近表明，热诱导的冷凝物是跨物种的刺激。我们捕获了酵母中的 Hsp70 底物，亚致死热休克诱导的冷凝物是 Hsp70。人类体内的底物，使细胞能够感知并响应这种发烧范围的温度，目前尚不清楚。在这些温度下，人体细胞中会凝结什么蛋白质，或者此类凝结物是否可能是 Hsp70 此外，在任何物种中，我们都缺乏对缩合物和 Hsp70 如何形成分子尺度的了解。我们准备利用生化、微观和化学的补充来准确地解锁这些知识。首先，我们将揭示人类细胞系在发烧范围内的蛋白质凝聚。温度，使用我们组已建立的沉降质谱法。使用单分子显微镜直接观察缩合物和 Hsp70 如何在分子尺度上相互作用。总之，这些目标将帮助我们从根本上阐明细胞如何感知和响应亚致死热休克。