Visualization and Quantification to Understand Cell Architecture in Biology

-A Study on Cytoplasmic Streaming Using PIV analysis-

Abstract

  The importance of visualization and quantification is increasing in the field of cell biology. We are studying the architecture of cell. After the visualization of intracellular structures through microscopes, we need to extract the velocity, size, and shape of such structures in a quantitative manner to investigate the underlying mechanisms. Here we introduce our research on cytoplasmic streaming, which is a type of intra-cellular transport widely seen in nature. We quantified the flow velocities of cytoplasmic streaming in the worm, Caenorhabditis eiegans, using particle image velocimetry (PIV). We then conducted a three-dimensional hydrodynamic simulation using the moving particle semi-implicit method. The simulation quantitatively reconstructed the quantified flow velocity distribution resolved through PIV analysis. These analyses demonstrated that the hydrodynamic properties of the cytoplasm are sufficient to mediate the forces generated by motor proteins to drive cytoplasmic streaming in animal cells.