Raj Paul

“Role of cytoskeletal mechanics in wound resistance in the giant ciliate protozoa Stentor coeruleus”

Advised by Prof. Sindy Tang

Abstract: The ability to heal wounds and regenerate is critical for single-cell organisms to seal membrane wounds in a timely manner to prevent loss of import cellular organelles. The giant single-cell ciliate protozoa Stentor coeruleus is known for its wound healing and regenerative abilities, having one of the highest healing rates among living organisms and being capable of healing large wounds. Stentor has been known to exhibit different mechanical modes to help them in the process of wound repair. In this work, we hypothesize that the Stentor cytoskeleton plays an important role not only in wound healing but also in resisting wounds. To elucidate the role of the cytoskeleton in wound resistance, we perturbed the cytoskeleton using drugs and flowed the cells through a microfluidic constriction to evaluate their wounding characteristics. Cells which were large relative to the constriction were more prone to wounding, and wounded cells failed to recover their aspect ratio post constriction. We also found that destabilization of the microtubule ribbons appeared to make the cells softer and increased the probability of wounding while decreasing the constriction time of the cells. Stabilizing the microtubules, on the other hand, appeared to make the cells stiffer and increased the constriction time of the cells. These cells also had an increased probability of wounding as compared to the control cells. Our findings have helped us understand how the unique cytoskeleton in Stentor helps the cell resist wounds and plays a critical role in its survival.