Cell Biology in the Advanced Lab: Diffusion, Flow, and Molecular Machines

Physics experiments with living cells can be an attractive addition to the advanced lab. Passive and active force generation, by diffusion, fluid flow, and mechanochemical energy transduction via motor proteins, can each be quantitatively studied using microscopy on live cells. In this talk, I present three exemplar experiments suitable for the advanced lab: (i) tracking particles in live onion cells and quantifying diffusive and ballistic (flow) components of the trajectories; (ii) tracking the motor protein kinesin and examining its velocity as a function of energy use; (iii) imaging mitosis in RPE cells and tracking the velocity of chromosome movement during cell division. Each of these experiments is done on a home-built, open-source microscope that is useful for teaching optics in the advanced lab as well. Finally, challenges for implementation will be discussed as well – in particular, the need for partnership with biochemists or cell biologists for materials and supplies – and I will present a bio-inspired alternative of purely diffusive, non-cellular, experiments.