The Investigation Of The Mechanobiology Of The Plasma Membrane Of Adherent Cells

As the interface between the cell and the extracellular microenvironment,the cell membrane is responsible for the exchange of materials and energy.The deformation and tension of the cell membrane directly affect many important subcellular-scale cellular physiological activities.Some research progress has been made in the experimental measurement of cell membrane local deformation and cell tension,but there is still a lack of quantitative measurement of local tension.Experimental studies on real cells are rarely reported,and most of the experimental data are obtained on simple cell-like bodies such as vesicles.In order to solve the problem of measuring the local deformation and tension of the cell membrane.This study establishes a new technology to quantify the deformation and tension of the cell membrane by measuring the reflection interference fringes,revealing the mechanism of the cell membrane deformation,extracting the characteristics of membrane biomechanical interference fringes of different cell lines.By combining the reflection interference contrast microscope with the traction force microscope,the study simultaneously measured the traction force exerted by the extracellular matrix on the cells,the local deformation and tension of the cell membrane.The measurement results obtained by the two techniques show that the cell membrane tension is consistent with the traction force.Meanwhile,the correlation between the dynamic behavior of the cytoskeleton structure and the local deformation of the cell membrane was observed by fluorescence imaging of living cells,the results showed that the integrity of the cytoskeleton structure and the contraction force of microfilament skeleton were beneficial to the formation of interference fringes of cell membrane.In addition,this study established a simple label-free cell typing technique,which uses the biomechanical characteristics of the reflection interference fringes of a variety of breast cancer cells as the basis for distinguishing cell subtypes.Finally,the molecular mechanism of stress fiber assembly in the microfilament skeleton is studied.Based on the hypothesis of indirect repulsion between different types of microfilament binding proteins through microfilament deformation,using a coarsegrained Kinetic Monte Carlo method to investigate the effect of the repulsion strength on the pattern formation of proteins along the stress fibers.The simulation results reproduce the dynamics of the cluster growth observed in experiments.Meanwhile,a double-S feature during the cluster growth were revealed.This study is helpful to study the response mechanism of the cell membrane under mechanical signal stimulation and the influence of the cytoskeleton.It also promotes the study of the interaction between cells,drugs and viruses.All in all,this project not only has important scientific significance in cross-field research,but also has potential clinical application value,which meets the current major social needs.