The Schlierf group has a strong background in single-molecule biophysics, in particular single-molecule FRET and force spectroscopy method development as well as application to dynamic structural biology questions.  Key research topics include DNA replication, DNA recombination and membrane protein structure and dynamics^1-5. In recent years, the group has been involved in defining community standards for data acquisition and analysis^6,7, developed large-throughput single-molecule methods⁸ and discovered increased structural dynamics in polypeptides through chaperone binding⁹ and mechanical regulation of DNA recombination¹⁰. In collaboration with the Alberti and the Jahnel labs, RNA structures and dynamics during protein interactions and in condensates are characterized, elucidating RNA regulatory mechanisms.

The Honigmann group uses fluorescence imaging, in vitro reconstitution and organotypic tissue culture to study the supramolecular organization and function of cell-cell interfaces ^1,2. They discovered that the formation of tight junctions is driven by surface condensation of ZO scaffold proteins with adhesion receptors at cell-cell contacts^3,4. Structural analysis suggests that surface condensation leads to the assembly of an ordered mesoscale structure made of molecular layers of receptors, scaffolds, adapters and the cytoskeleton. Within the framework of the RTG, the Honigmann group will combine molecular reconstitutions and single molecule imaging with polymer physics to study how the surface condensation of scaffold proteins couples to conformational changes of proteins that are important for cortex regulation.

The Grill group bridges experiment with theory in the physics of life, in particular active matter physics, morphogenesis, the actomyosin cytoskeleton, and biomolecular condensates. Key research questions addressed concern the force balance that underlies actomyosin cortical flows¹, symmetry breaking in active matter systems^2–4, active chiral matter and left/right symmetry breaking⁴. In collaboration with the Jülicher group in Dresden the Grill group has, through its long-lasting expertise in using optical tweezers in a single molecule and a mesoscale context⁵, investigated protein-DNA co-condensation⁶, discovered a dynamic instability of cortical condensates in the context of actomyosin cortex activation⁷, and together with the Hyman and Jülicher groups discovered a DNA-sequence-dependent prewetting transition towards droplet of general transcription factors on DNA⁸.

The Brugués group has a strong background in biophysics, combining both theory and experiments. From the experimental side the Brugués lab uses cytoplasmic extracts, in vivo measurements and in vitro reconstitution. Key research topics have included co-condensation of DNA and protein interactions^1,2, methods to quantitatively measure protein concentration in condensates³, reconstitution of chromatin processes in single DNA strands⁴, and self-organization and mechanics of the mitotic spindle as an active liquid droplet^5-8. In recent years, the group has developed a theoretical framework for polymers in mixed solvents which explaining unusual phase transition scenarios. In collaboration with the Alberti and Jahnel groups, we have demonstrated that capillary-like forces arising from DNA-protein interactions play a key role in DNA damage².