CAREER:The role of nuclear biomechanics during cell migration in 3-D environments

职业：核生物力学在 3D 环境中细胞迁移过程中的作用

• 批准号: 1254846
• 负责人: Jan Lammerding
• 金额: $ 40万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2020-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1254846&HistoricalAwards=false
• 关键词: CAREER; role; nuclear; biomechanics; during

PI: Lammerdng. JanProposal ID: 1254846Intellectual Merits: While cell migration on 2-dimensional (2-D) substrates has been studied for many decades, the physical challenges cells face when moving in 3-D environments are only beginning to emerge now. The central hypothesis of this proposal is that deformation of the large and stiff nucleus presents a rate-limiting step during migration through tight constriction encountered in 3-D environments such as extracellular matrixes or during intra- or extravasation. This project will address to what extent the deformability of the nucleus governs the transit of cells through narrow constrictions by monitoring cells as they migrate through microfluidic channels with defined constrictions while visualizing subcellular deformations and transit efficiency. In addition, ablation of cytoskeletal filaments with femtosecond laser pulses as cells pass through narrow constrictions will be used to determine whether the nucleus is being pulled or pushed by the cytoskeleton to overcome its resistance when squeezing through constrictions smaller than the size of the nucleus. Complementing these experiments, molecular sensors engineered from modified nuclear envelope proteins that report tensile forces and localized compression at the nuclear envelope by changes in fluorescence intensity or fluorescence resonance energy transfer (FRET) efficiency will be applied to cells during 3-D migration to quantify the cytoskeletal forces acting on the nucleus during 3-D migration and visualize their distribution along the nuclear periphery.Broader Impact:The research activities will be complemented with a comprehensive education and outreach program that builds on simplified models of the proposed research to introduce middle and high school students to biomedical engineering, with the goal of increasing participation of female students in science, technology, engineering, and math (STEM) subjects. Tapioca pearls, the key ingredient of the popular bubble tea, will be used as safe, easily accessible, and inexpensive stand-in for biological cells, while simple 'millifluidic' devices replace technically demanding microfluidics designs to probe cellular biomechanics. These 'tapioca millifluidics' experiments, along with accompanying lectures, will be introduced to students from underserved middle and high schools as part of existing and novel outreach programs at Cornell University that target high school girls and underrepresented minorities to provide them with hands-on experiences in biomedical engineering to boost confidence, meet role models, and overcome gender stereotypes. An additional education component is the creation of an online portal for self-directed learning to address the challenge of teaching interdisciplinary biomedical engineering courses to students with diverse academic backgrounds.

PI：Lammerdng. JanProposal ID：1254846智力优点：虽然细胞在二维（2-D）基质上的迁移已经研究了几十年，但细胞在3-D环境中移动时所面临的物理挑战现在才开始出现。这个建议的中心假设是，变形的大和僵硬的核提出了一个限速步骤，在迁移过程中遇到的3-D环境中，如细胞外基质或在内部或外渗的紧密收缩。该项目将解决细胞核的变形能力在多大程度上控制细胞通过狭窄的收缩，通过监测细胞迁移通过具有限定收缩的微流体通道，同时可视化亚细胞变形和运输效率。此外，当细胞通过狭窄的收缩时，用飞秒激光脉冲消融细胞骨架细丝将用于确定细胞核是否被细胞骨架拉动或推动，以克服当挤压通过小于细胞核尺寸的收缩时的阻力。作为这些实验的补充，由修饰的核膜蛋白质工程化的分子传感器，其通过荧光强度或荧光共振能量转移（FRET）效率的变化报告核膜处的张力和局部压缩，将在3-D迁移期间应用于细胞，以量化3-D迁移期间作用于细胞核的细胞骨架力。D迁移，并可视化它们沿核周边的分布沿着。研究活动将辅之以全面的教育和外展计划，该计划以拟议研究的简化模型为基础，向初高中生介绍生物医学工程，目标是增加女学生对科学、技术的参与，工程，数学（STEM）科目。木薯珍珠是受欢迎的泡泡茶的关键成分，将被用作安全，易于获取和廉价的生物细胞替代品，而简单的“毫流体”设备将取代技术要求高的微流体设计来探测细胞生物力学。这些“木薯millifluidics”实验，沿着伴随着讲座，将被介绍给来自服务不足的初中和高中的学生，作为康奈尔大学现有和新颖的外展计划的一部分，该计划针对高中女生和代表性不足的少数民族，为他们提供生物医学工程方面的实践经验，以增强信心，满足榜样，并克服性别陈规定型观念。另一个教育组成部分是创建一个自我导向学习的在线门户网站，以应对向具有不同学术背景的学生教授跨学科生物医学工程课程的挑战。