Understanding Why Cells Choose to Migrate Towards the Cathode: Directing Cell Motility Using Electric Fields

细胞如何感知、响应和接近或远离外部信号是许多生物和医学现象的核心，包括胚胎发生、形态发生、免疫反应、伤口愈合和癌症转移。趋电性是指细胞响应外部电场而使其运动方向偏向的现象，在许多细胞过程中都很重要；然而，电场如何影响细胞内细胞骨架组织的潜在物理机制尚不清楚。计划研究的总体目标是确定细胞中启动电趋向性的物理机制。该目标将通过使用精确的微流体电池约束室观察电致迁移和量化电致电池周围的离子活性来实现。智力价值是基于创新的策略和在确定细胞电趋向性过程中电场转化为下游化学信号的物理切入点方面的基本意义。与关注下游信号蛋白的传统电趋向性研究不同，该项目侧重于了解电场对细胞膜的直接影响。通过为本科生和研究生提供新课程和实验室培训，通过机构的“工程创新”计划向高中生推广，通过巴尔的摩和查尔斯市中学的“科学学院技术”计划吸引6 - 8年级学生，并通过实践研究和社区推广扩大未被充分代表的群体参与拟议的研究项目，从而实现教育影响。细胞如何感知、响应和接近或远离外部线索是许多生物学和医学现象的核心，包括胚胎发生、形态发生、免疫反应、伤口愈合和癌症转移。许多真核细胞具有内部罗盘，使它们能够感知这些信号，通常以化学引诱剂、电压或机械应力的梯度形式出现，并使它们的运动偏向特定方向。趋电性是指细胞响应外部电场而使其运动方向偏向的现象，在许多细胞过程中都很重要；然而，电场如何被传导到细胞中以影响细胞骨架组织的潜在物理机制尚不清楚。本提案的总体目标是确定负责启动细胞中电趋向性的相关物理机制。该目标将通过使用精确的微流体电池约束室观察电致迁移和量化电致电池周围的离子活性来实现。具体目标是：1)开发和构建微流体约束几何结构，用于在电趋向性过程中分析细胞膜上的电动离子通量；2)量化电趋向性过程中电场诱导的膜过程，包括离子流和离子通道活性；3)了解这些上游电场诱导的事件如何激活和转导下游细胞信号。计划研究的智力价值是基于创新的策略和在确定细胞电趋动过程中电场转导成下游化学信号的物理切入点方面的基本意义。与关注下游信号蛋白的传统电趋向性研究不同，该项目侧重于了解电场对细胞膜的直接影响。通过为本科生和研究生提供新课程和实验室培训，通过机构的“工程创新”计划向高中生推广，通过巴尔的摩和查尔斯市中学的“科学学院技术”计划吸引6 - 8年级学生，并通过实践研究和社区推广扩大未被充分代表的群体参与拟议的研究项目，从而实现教育影响。

PI: Gagnon, Zachary RProposal #: 1605553How a cell senses, responds, and moves towards or away from an external cue is central to many biological and medical phenomena including embryogenesis, morphogenesis, immune response, wound healing and cancer metastasis. Electrotaxis, the phenomenon by which cells bias their motion directionally in response to an externally applied electrical field, is important in a number of cellular processes; however, the underlying physical mechanism of how electric fields influence cytoskeletal organization within the cell is unknown. The overall goal of the planned research is to determine the physical mechanisms responsible for initiating electrotaxis in cells. The goal will be achieved by observing electrotactic migration and quantifying the ion activity surrounding electrotaxing cells using precise microfluidic cell confinement chambers. Intellectual merit is based on the innovative strategy and fundamental significance in determining the physical entry point where electric fields are converted into a downstream chemical signal during cellular electrotaxis. Unlike traditional electrotaxis work that focuses on downstream signaling proteins, this project focuses on understanding the immediate influences of the electric field at the cell membrane. Educational impact is achieved through providing new courses and laboratory training for undergraduate and graduate students, outreach to high school students through the institutions "Engineering Innovation" program, engaging 6th - 8th grade students through the "Science Academy Technology" program in Baltimore and Charles City Middle Schools and broadening the participation of underrepresented groups in the proposed research projects through hands-on research and community outreach.How a cell senses, responds, and moves towards or away from an external cue is central to many biological and medical phenomena including embryogenesis, morphogenesis, immune response, wound healing and cancer metastasis. Many eukaryotic cells have internal compasses that allow them to sense these cues, often in the form of gradients of chemoattractant, voltage, or mechanical stress, and bias their motion in a specific direction. Electrotaxis, the phenomenon by which cells bias their motion directionally in response to an externally applied electrical field, is important in a number of cellular processes; however, the underlying physical mechanism of how electric fields are transduced into the cell to influence cytoskeletal organization is unknown. The overall goal of this proposal is to determine the relevant physical mechanisms responsible for initiating electrotaxis in cells. The goal will be achieved by observing electrotactic migration and quantifying the ion activity surrounding electrotaxing cells using precise microfluidic cell confinement chambers. The specific objectives are: 1) to develop and build microfluidic confinement geometries for cell membrane level analysis of electrokinetic ion flux during electrotaxis, 2) to quantify the electric field-induced membrane processes including ion-flow and ion channel activity during electrotaxis, and 3) to understand how downstream cell signaling is activated and transduced by these upstream electric field-induced events. The intellectual merit of the planned research is based on the innovative strategy and fundamental significance in determining the physical entry point where electric fields are transduced into a downstream chemical signal during cellular electrotaxis. Unlike traditional electrotaxis work that focuses on downstream signaling proteins, this project focuses on understanding the immediate influences of the electric field at the cell membrane. Educational impact is achieved through providing new courses and laboratory training for undergraduate and graduate students, outreach to high school students through the institutions "Engineering Innovation" program, engaging 6th - 8th grade students through the "Science Academy Technology" program in Baltimore and Charles City Middle Schools and broadening the participation of underrepresented groups in the proposed research projects through hands-on research and community outreach.