Ke Xu Group

Our Research

Living systems achieve versatile structural organizations and amazing orders. Our research aims at understanding how orders emerge in biological systems at the nanometer-scale from the interaction between biomolecules, and we achieve this goal experimentally through physicochemical approaches:

a) To interrogate cellular processes at the nanoscale through the development and synergistic application of innovative (bio)physical and chemical methods. In particular, super-resolution fluorescence microscopy (optical nanoscopy) represents a major effort of our research: our recent work just pushed the limit of optical resolution to below 10 nm (Nature Methods 9, 185), and this opens up exciting new opportunities to address questions that were previously unanswerable (our recent example: Science 339, 452).
b) A systems approach to interpret complex cellular processes on the basis of fundamental physical and chemical principles, e.g., diffusion, local reactions, self-organization, and feedback loops, again at the nanoscale.

Specific examples include: (1) Local (nanoscale) structural changes in neurons that lead to the emergence of a single axon but multiple dendrites from a neuron during development. (2) Polarization of cells of the immune system (e.g., white blood cells) under controlled local chemical signals. (3) In vitro (bio)chemical systems as models for cellular processes involving symmetry breaking and emergence of patterns, e.g., cell polarization, motility and development. (4) Combination of advanced imaging methods, including super-resolution microscopy and single-molecule imaging/tracking, with other modern physicochemical tools and concepts, including nanomaterials, nanofabrication and self-assembly, to simultaneously manipulate and probe cells with nanometer-precision.