Abstract
Cellular structures are hydrodynamically interconnected, such that force generation in one location can move distal structures. One example of this phenomenon is cytoplasmic streaming, whereby active forces at the cell cortex induce streaming of the entire cytoplasm. However, it is not known how the spatial distribution and magnitude of these forces move distant objects within the cell. To address this issue, we developed a computational method that used cytoplasm hydrodynamics to infer the spatial distribution of shear stress at the cell cortex induced by active force generators from experimentally obtained flow field of cytoplasmic streaming. By applying this method, we determined the shear-stress distribution that quantitatively reproduces in vivo flow fields in Caenorhabditis elegans embryos and mouse oocytes during meiosis II. Shear stress in mouse oocytes were predicted to localize to a narrower cortical region than that with a high cortical flow velocity and corresponded with the localization of the cortical actin cap. The predicted patterns of pressure gradient in both species were consistent with species-specific cytoplasmic streaming functions. The shear-stress distribution inferred by our method can contribute to the characterization of active force generation driving biological streaming.
Highlights
Cellular components require proper positioning to perform their functions within the cell
We developed a computational method that used cytoplasm hydrodynamics to infer the spatial distribution of shear stress at the cell cortex induced by active force generators from experimentally obtained flow field of cytoplasmic streaming
We established a computational method for inferring the localization of active force generators based on live-imaging data of the flow field in cytoplasmic streaming
Summary
Cellular components require proper positioning to perform their functions within the cell. Cytoplasmic streaming is described in several types of animal and plant cells as hydrodynamic motion driven by active force generators at the cell cortex [3,4,5,6,7,8,9,10]. These generators undergo oriented movement at the cell cortex, inducing shear stress that drives movement of the entire cytoplasm. The shear-stress distribution should directly reflect the position and magnitude of active force generation, but its characterization is challenging
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have