CAREER: Controlling molecular enrichment in biomolecular condensate materials

非技术总结：了解自然发生的生物材料是为社会挑战设计新的更好的材料的关键一步。近年来，生物分子凝聚物，由蛋白质和其他大分子组成的自组装细胞区室，已经引起了人们的极大兴趣，因为它们已经被证明是细胞中各种生化反应的原因。由于其性质是柔软的生物材料，并具有可变的生物化学特性，某些冷凝物材料已被证明可以富集溶质;然而，驱动富集的基本材料和化学特性尚不清楚。在本项目中，我们将量化冷凝物中的溶质富集，并使用具有可调组成和相互作用的模型冷凝物系统将这种富集与冷凝物中的物理化学和机械性质联系起来。这些数据将是必不可少的，在制定规则，定制浓缩物富集不同的分子类相关的药物输送和工业催化应用。 拟议的项目还将侧重于劳动力发展，具体做法是针对研究行业中代表性不足的两个群体（第一代高中生和应征军人）开设光学显微镜实用课程。我们的目标是提供一条在动手环境中学习光学的途径，在这种环境中，直觉和概念是通过“做”来建立的。PI将在当地高中和军事设施提供每月课程，感兴趣的个人将有机会在使用显微镜时制作显微镜。完成本课程后，参与者将有机会在UT Austin的实验室中担任类似于REU的指导暑期研究员，以了解他们的技能如何转化为前沿研究。技术总结：生物分子凝聚物是富含蛋白质和动态无膜的生物材料，已被证明在不同的亚细胞过程中发挥关键作用，如膜运输和转录调控。最近的研究表明，冷凝物可以富集溶质，特别是化疗药物和其他小分子。然而，这种浓缩的理由仍然是众所周知的。分子的分配是基于亲合力还是结合位点的数量？凝聚物中蛋白质的机械性质或相互联系如何影响溶质富集？该CAREER项目的目的是澄清内部冷凝物环境，特别是蛋白质密度和蛋白质-蛋白质相互作用如何影响疏水性和亲水性溶质的溶质富集。该项目将使用一系列定量原位显微镜来评估由静电（LAF-1）或各种短程相互作用（FUS）稳定的两个模型冷凝物系统的内部冷凝物环境，其中蛋白质密度和连接性可以独立控制。建立在不同类型的冷凝液中的溶质富集的亲水性和疏水性溶质的控制参数将允许开发预测模型，以定制这些生物材料的特定应用。在这项研究中，PI将建立一个实用的，动手的光学显微镜课程，旨在建立信心，并提供技术经验，以两个历史上代表性不足的群体在研究：即将成为第一代高中毕业生和入伍的军事人员。除了本课程，还将设立一个新的指导研究项目，为课程参与者提供在材料科学和显微镜实验室工作的机会，以扩大接触尖端研究环境的人群。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Non-Technical Summary: Understanding naturally occurring, biological materials is a critical step toward designing new, better materials for societal challenges. In recent years, biomolecular condensates, self-assembled cellular compartments composed of proteins and other macromolecules, have garnered significant interest as they have been shown to be responsible for various biochemical reactions in cells. Being soft biological materials by their nature, and having variable biochemical properties, certain condensate materials have been shown to enrich solutes; however, the fundamental material and chemical properties that drive enrichment are unknown. In this project, we will quantify solute enrichment into condensates and relate this enrichment with physical chemical and mechanical properties in condensates using model condensate systems with tunable composition and interactions. These data will be essential in developing rules to customize condensates for enrichment of different molecule classes relevant for drug delivery and industrial catalytic applications. The proposed project will also focus on workforce development through implementation of a practical course in optical microscopy targeted at two communities that are underrepresented in the research industry: first generation high school students and enlisted military personnel. Our goal is to provide a path to learning about optics in a hands-on environment where intuition and concepts are built by “doing”. The PI will offer monthly courses at local high schools and military installations in the area where interested individuals will be given the chance to build a microscope as they use it. Following completion of this course, participants will be given the opportunity to work as mentored summer researchers, similar to an REU, in labs at UT Austin to see how their skills translate into cutting-edge research. Technical Summary: Biomolecular condensates are protein-rich and dynamic membrane-less biomaterials that have been shown to play critical roles in different subcellular processes such as membrane trafficking and transcriptional regulation. Recent studies have shown that condensates can enrich solutes, specifically chemotherapeutics and other small molecules. However, the rationale for such enrichment remains known. Do molecules partition based on avidity, or number of binding sites? How do the mechanical properties or interconnectedness of proteins in condensates affect solute enrichment? The objective of this CAREER project is to clarify how the intra-condensate environment, specifically protein density and protein-protein interactions affect solute enrichment for hydrophobic and hydrophilic solutes. This project will use an array of quantitative in situ microscopies to evaluate the intra-condensate environment for two model condensate systems stabilized by electrostatic (LAF-1) or various short-range interactions (FUS) in which the protein density and connectivity can be independently controlled. Establishing the governing parameters for solute enrichment in different types of condensates for both hydrophilic and hydrophobic solutes will allow development of predictive models to customize these biomaterials to specific applications. During this research, the PI will establish a practical, hands-on optical microscopy course aimed at building confidence and providing technical experience to two historically underrepresented groups in research: soon-to-be first-generation high school graduates and enlisted military personnel. In addition to this course, a new mentored research program will be established to give course participants the opportunity to work in materials science and microscopy labs to broaden the population that has access to cutting-edge research environments.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.