Chih-Hsuan Lai (Academia Sinica): Structures and functional dynamics of topologically knotted proteins

Topologically knotted proteins arise from threading events during protein folding, but how protein knots contribute to protein dynamics, functions, and stability remains sparsely explored. To address this issue, we have systematically used NMR spectroscopy, X-ray crystallography, and AlphaFold (AF) tools to investigate intricately knotted proteins, including human 52-knotted ubiquitin C-terminal hydrolases (UCHs), and bacterial 71-knotted proteins. We showed how disease mutations negatively impact the deubiquitinase activity and alter the dynamics. Specifically, we have developed an experimental workflow to illustrate how a minimal structural perturbation of the allosteric network within the UCH domain of BAP1 would lead to profound functional impact on the DUB activity. We further experimentally verify the AF-predicted 71-knotted structure of Q9PR55 that has not been seen in the literature, illustrating the unprecedented predictive power of AlphaFold. Our experimental findings have paved the foundation for rational designs of artificial knotted proteins with novel functional modalities.

Zoom Information:

https://us02web.zoom.us/j/2022111100

(Meeting code: 2022111100 Password: skcm2)