Biophysical Society Thematic Meeting | Tutzing 2026

Single-Molecule FRET: The Next 30 Years

Tuesday Speaker Abstracts

QUANTITATIVE INVESTIGATIONS OF COMPLEX MOLECULAR MACHINES USING SMFRET: WHAT WE HAVE LEARNED AND WHERE ARE WE GOING Scott C. Blanchard ; 1 St. Jude Children's Research Hospital, Structural Biology, Chemical Biology & Therapeutics, Memphis, TN, USA Static structures determined by crystallography and cryo-EM have transformed our understanding of the molecules of life. The power of single-molecule methods is to add the dimension of dynamism to these snapshots to reveal the nature, order and timing of structural processes underpinning function. For over two decades our group has worked alongside structural biologists, cell biologists, and pharmacologists to examine biomolecular metastability and how transitions between states are impacted by disease mutations and therapeutic interventions. Single-molecule FRET has been central to this pursuit. By resolving conformational dynamics one molecule at a time, it becomes possible to identify rate-limiting steps in function across machines spanning many orders of magnitude in mass, and to see how mutations and small molecules reshape energy landscapes in ways that static views cannot reveal. This mechanistic layer is where much of the molecular basis of human disease ultimately resides. Alongside advances across the field, our team has focused on widening the resolution, sensitivity and reproducibility of single-molecule fluorescence measurements. Hidden Markov approaches, adapted from the ion-channel community, brought statistical rigor to the interpretation of conformational trajectories; sCMOS detection improved throughput and time resolution; self-healing fluorophores extended the sensitivity, accuracy, and observation times attainable; and parallelized, rapid-exchange measurement suppresses experimental variances to reveal functional distinctions between closely related systems. Together with findings from many laboratories, our results make an increasingly clear case that dynamism is fundamental to biomolecular function and governing dynamism is essential to regulation. Understanding the evolutionary constraints that shape and tune the dynamic properties of biomolecules is a critical and largely unexplored frontier on the road ahead. Efforts toward this frontier will be discussed alongside new findings that naturally occurring sequence variation, chemical modification, and cellular context tune the dynamic landscapes of biomolecular machines and how these features may be understood and therapeutically engaged.

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