The Rosalind Franklin Institute is welcoming Professor Mark Lake on Thursday 18th June from 13:00 – 14:00.

RAL site pass holders are welcome to attend in person (no registration required) in the Franklin’s first floor Hub. To join in person, please arrive in the R113 Franklin foyer at least 5 minutes before the start of the seminar and a member of the team will let you into the building.

Talk title:

From DNA Chirality to Bacterial Condensates: Single-Molecule Biophysics of Topology, Mechanics and Phase Separation

Abstract:

Symmetry breaking underpins life across scales, from molecular chirality to mesoscale cellular organisation. We combine cutting-edge single-molecule manipulation and live-cell imaging to reveal how physical principles of twist, topology and phase separation govern biological function.

Using our breakthrough COMBI-Tweez technology, which integrates optical and magnetic tweezers with nanoscale fluorescence microscopy, we simultaneously control and measure twist, extension and topology of individual DNA molecules in real time. This enables direct observation of reversible plectoneme formation, mechanical responses under physiological force and torque, and protein-induced perturbations of DNA topology, as well as the engineering of braided DNA as a ‘DNA rope’ smart biomaterial.

In parallel, we uncover how bacterial aggresomes—mesoscale membraneless condensates formed by liquid–liquid phase separation—safeguard mRNA during stress. New data reveals that ribosomal proteins L2 and L15 reciprocally tune the condensate’s state of fluidification, modulating mRNA protection and cellular recovery.

Together, these approaches reveal features of a unified biophysical framework linking molecular chirality, mechanics and phase behaviour to cellular resilience and function.

Biography:

Prof Mark Leake is a physicist by training, addressing challenging biophysical and biochemical questions in a range of biological processes. He gained his biophysics PhD on muscle proteins using optical tweezers in King’s College London, later postdoctoral positions in Oxford and Heidelberg, and independence as a Royal Society URF in Oxford, leading research in single-molecule biophysics, prior to becoming Anniversary Chair of Biological Physics at the University of York in 2013.

Mark was Director-Founder of the Biological Physical Sciences Institute and is Coordinator of the Physics of Life Group in the University of York and Chair of the UK Physics of Life network PoLNET. His research involves developing new single-molecule optical microscopy instrumentation for addressing open biological questions and coupling these to molecular biology/biochemistry to investigate single biomolecules under physiologically relevant environments.

To watch the seminar online, please sign up via the link below.

RAL site pass holders are welcome to attend in person (no registration required) in the Franklin’s first floor Hub. To join in person, please arrive in the R113 Franklin foyer at least 5 minutes before the start of the seminar and a member of the team will let you into the building.