Biophysical Control of Cell Form and Function by Single Actomyosin Stress Fibers

单个肌动球蛋白应力纤维对细胞形态和功能的生物物理控制

• 批准号: 10445792
• 负责人: Sanjay Kumar
• 金额: $ 33.06万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-20 至 2026-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10445792
• 关键词: 3-Dimensional; Actins; Actomyosin; Address; Adopted; Architecture; Award; Back; Biological; Biophysics; Cell Nucleus; Cell Shape; Cells; Cellular Structures; Clinical; Collaborations; Complex; Computer Models; Confined Spaces; Cues; Dependence; Disease; Dorsal; Engineering; Environment; Extracellular Matrix; Fiber; Foundations; Genetic; Genetic Transcription; Geometry; Glioblastoma; Glioma; Image; Individual; Knowledge; Lasers; Maintenance; Malignant neoplasm of brain; Measures; Mechanics; Mediating; Mesenchymal; Methodology; Microfluidic Microchips; Microfluidics; Molecular; Morphogenesis; Myosin ATPase; Neurosurgeon; Nuclear; Pathway interactions; Pattern; Phosphatidylinositol 4,5-Diphosphate; Phosphorylation; Physiology; Play; Process; Publications; Regulation; Resistance; Role; Shapes; Signal Transduction; Stress Fibers; Surface; Technology; Testing; Tissues; Transcription Coactivator; Translating; Width; Work; base; bevacizumab; cell motility; cofilin; design; human disease; in vivo; innovation; insight; migration; mimetics; monolayer; mouse model; multi-scale modeling; nanosurgery; network architecture; novel; optogenetics; reconstitution; recruit; stem cells; tool; two-dimensional

PROJECT SUMMARY/ABSTRACT Actomyosin stress fibers (SFs) enable cells to tense the extracellular matrix (ECM), a process key to cell shape determination, motility, and morphogenesis. Over the past 15+ years, including the past period of R01 support, we have made significant contributions to the field’s understanding of SF mechanics and contributions to cell structure. Our work is particularly notable for the use of femtosecond laser nanosurgery (FLN), which has enabled us to show that the three canonical SF subtypes – dorsal fibers, transverse arcs, and ventral fibers – collectively enforce a front-back tension gradient that underlies two-dimensional (2D) mesenchymal migration. We also showed that the SF network architecture can mechanically reinforce individual SFs, which has significant implications for symmetry breakage during directed migration and force propagation through cell monolayers. With this intellectual foundation in place, our renewal application turns to two important questions: How is polarization of tension in the SF network encoded by molecular signals classically understood to establish front-back polarity? And how does our knowledge of 2D SF networks translate to confined migration geometries like those found in tissue? We will address these questions through two specific aims, both of which build upon publications from this award. In Specific Aim 1, we will investigate mechanistic contributions of cofilin-1 to establishment and maintenance of SF front-back tension polarization during migration. We hypothesize that cofilin-1 establishes front-back polarization of SF tension by promoting the assembly and contractile maturation of transverse arcs. By combining biophysical, engineering, and cell biological tools, we will identify key molecular and force-based signals that modulate recruitment of cofilin-1 to developing transverse arcs. In an innovative new collaboration with Dr. Bruce Goode (Brandeis) we will reconstitute actin bundles in microfluidic devices and quantify the relationship between tensile force and cofilin- 1 engagement. In Specific Aim 2, we will dissect contributions of SF networks to migration in confined geometries where the ECM imposes axial cues and sterically precludes elaboration of 2D SF networks. We hypothesize that increasing confinement redirects SF assembly from the 2D dorsal fiber-transverse arc-ventral fiber assembly pathway towards de novo parallelized SF assembly. We will combine microengineered culture platforms, single-cell mechanical tools, and superresolution imaging to probe confinement-induced changes in SF assembly, architecture, and mechanics. Aim 2 will leverage two established, productive collaborations: With Dr. Ulrich Schwarz (U. Heidelberg), we will develop multiscale computational models that relate SF network architecture and mechanics to cell migration in confined spaces. With neurosurgeon Dr. Manish Aghi (UCSF), we will test the clinical value of our observations by asking if confined migration of glioblastoma stem cells is retrospectively predictive of in vivo invasion patterns. Our studies will create unprecedented new insight into how SFs contribute to migration, with innovative methodology and close connection to human disease.

项目概要/摘要 肌动球蛋白应力纤维 (SF) 使细胞能够拉紧细胞外基质 (ECM)，这是细胞形状的关键过程 过去 15 年多的时间里，包括 R01 的过去时期。 支持，我们为该领域对 SF 机制的理解和贡献做出了重大贡献 我们的工作特别值得注意的是飞秒激光纳米手术（FLN）的使用，它 使我们能够证明三种典型的 SF 亚型——背侧纤维、横弧和腹侧纤维 纤维 – 共同强化二维 (2D) 间充质基础的前后张力梯度 我们还表明，SF 网络架构可以机械地增强各个 SF，从而实现迁移。 对细胞定向迁移和力传播过程中的对称性破坏具有重大影响 有了这个知识基础，我们的更新应用就转向了两个重要的方面。 问题：SF 网络中的张力极化是如何由分子信号经典编码的 我们对 2D SF 网络的了解如何转化为建立前后极性？ 我们将通过两个方面来解决这些问题： 具体目标，这两个目标均以该奖项的出版物为基础，在具体目标 1 中，我们将进行调查。 cofilin-1对SF前后张力极化建立和维持的机制贡献 我们研究了 cofilin-1 通过促进 SF 张力的前后极化。 通过结合生物物理、工程学和细胞，横向弧的组装和收缩成熟。 生物工具，我们将识别关键分子和基于力的信号，调节 cofilin-1 的募集 在与 Bruce Goode 博士（Brandeis）的创新合作中，我们将开发横向弧。 在微流体装置中重建肌动蛋白束并量化张力和丝丝蛋白丝切蛋白之间的关系 1 参与度 在具体目标 2 中，我们将剖析 SF 网络对受限移民的贡献。 ECM 施加轴向线索并在空间上排除了 2D SF 网络的阐述。 培养增加限制将 SF 组装从 2D 背侧纤维横弧腹侧重定向 通往从头并行 SF 组装的纤维组装途径我们将结合微工程培养。 平台、单细胞机械工具和超分辨率成像来探测限制引起的变化 SF 装配、架构和机械将利用两个已建立的、富有成效的合作： 我们将与 Ulrich Schwarz 博士（海德堡大学）一起开发与 SF 相关的多尺度计算模型 与神经外科医生 Manish Aghi 博士合作研究有限空间内细胞迁移的网络架构和机制。 （加州大学旧金山分校），我们将通过询问胶质母细胞瘤干是否局限性迁移来测试我们观察的临床价值 细胞对体内侵袭模式进行回顾性预测，我们的研究将创造前所未有的新见解。 探讨 SF 如何通过创新方法以及与人类疾病的密切联系来促进移民。