Sheung Lab

Eukaryotic cells rely on far-from-equilibrium processes, some of which call for targeted transport of molecules in a dynamic, complex, and crowded environment to sustain life. Cell division, intracellular signaling, and cell growth are just some of the foundational cellular functions which rely on emergent transport mechanisms with no passive equivalent. This project aims to advance our understanding of intracellular transport by investigating the dynamics of passive biological molecules, such as DNA, in active cytoskeleton composite substrates.

We are interested in the mechanics of active cytoskeletal systems and how the interplay between motor activity, the composite nature of the cytoskeleton, and time-varying structure leads to the myriad mechanical properties that cells exhibit. To investigate these properties, our lab couples optical tweezers microrheology with fluorescence microscopy to elucidate the effects of motor activity on the mechanics and structure of active actin−microtubule composites. 

Optical imaging has seen revolutionary gains over the past decade, in areas such as resolution, stability, number of targets simultaneously visualized, and affordability, just to name a few. In accordance with these trends, we have designed and constructed custom, state of the art optical instruments in this lab for our own research. Students get guided, hands-on experience through the development and upkeep of these systems, then help establish pedagogy to share these resources and imaging expertise with other biologists.