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. 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.
