We use interdisciplinary methodologies to investigate the cell biology, biophysics, and biochemistry of mitosis. Trainees can obtain rigorous training encompassing molecular and cell biological methods, biochemistry, quantitative imaging, image analysis, and mathematical modeling. Don’t hesitate to contact the PI to learn more!

1. Systems biology of the mitotic checkpoint

The human kinetochore is an incredibly complex protein machine. It consists of hundreds of copies and more than ten different protein complexes. These proteins work together to implement three other functions: (1) a mechanical motor, (2) tension-sensitive regulatory mechanisms, and (3) signaling (see #2 below). How does the kinetochore integrate these functions into a conserved protein framework? Does the nanoscale organization of the kinetochore play a role in this integration? The Joglekar lab has been at the forefront of developing fluorescence microscopy assays to define the nanoscale architecture of the kinetochore. We have initiated the next research phase: the use in vivo imaging to study the mechanics of kinetochore movement.

2. Perturbation and adaptation of the mitotic checkpoint in cancer biology

The mitotic checkpoint is a composite system consisting of biochemical sub-systems: (1) a mechanical switch that turns on and off: (2) a biochemical signaling cascade, which conveys the state of the mechanical switch (3) a biochemical switch that controls a cell-cycle transition. Investigation of this complex composite system falls mainly into two categories: (A) identifying proteins, protein-protein interactions, and their regulation, and (B) computational analysis aimed at understanding the overall design of the signaling cascade. We have opened a new front: using extensive, quantitative analysis of the individual biochemical reactions in vivo to build a detailed mathematical model of the mitotic checkpoint. Our work relies heavily on CRISPRed cell lines to label various signaling proteins involved in the mitotic checkpoint and a range of live-cell fluorescence microscopy methods.

3. Reverse engineer kinetochore-like machines using de novo-designed proteins.

This is an exciting new front. Decades worth of investigations of the kinetochore have built a complete picture of its structure, function, and regulation. What comes next? We are pioneering efforts to reverse engineer the kinetochore using de novo-designed proteins. This project will rely heavily on a combination of in vivo and in vitro investigations with applied protein design.