Prof. Megan Angela Steves, University of California Berkeley, "Multidimensional widefield single-molecule microscopy beyond the camera frame rate"
- Event Type
- Seminar/Symposium
- Sponsor
- School of Chemical Sciences
- Location
- 1024 Chemistry Annex
- Date
- Jan 14, 2026 10:00 - 11:30 am
- Contact
- Randy Prince
- rlprince@illinois.edu
- Phone
- 217-333-2540
Single-molecule localization microscopy (SMLM) offers opportunities for spatially mapping physico-chemical parameters with super-resolution. Molecular motion is one such parameter that can be encoded in SMLM, providing insight into local environment and interactions. However, single-molecule tracking has generally been limited to relatively slow-moving molecules due to slow detector frame rates (~10 ms). In this talk, I will discuss our development of SpeedyTrack (spatially-encoded dynamics tracking), which overcomes this barrier by projecting multiple observations from different time points to the spatial domain by capitalizing on the fast vertical clocks of EMCCDs, achieving <50 μs temporal resolution.
With this newly accessible spatiotemporal regime, we have tracked the fast diffusion of ATP and its non-specific interactions with proteins, revealing specific ion effects which reflect the interplay of hydrophobic and electrostatic components in this interaction. In live cells, we have resolved the motion of proteins in the endoplasmic reticulum, answering a long-standing open question about the predominance of active vs. passive transport mechanisms. Beyond molecular motion, the principle of SpeedyTrack offers opportunities for spatially-encoding other dimensions, such as spectra or polarization, for super-resolution imaging. I will briefly discuss our ongoing work to encode excitation spectra into single-molecule images using cyclic laser excitation.