Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
BP: Fachverband Biologische Physik
BP 29: Posters - Multi-Cellular Systems
BP 29.9: Poster
Dienstag, 21. März 2017, 14:00–16:00, P2-EG
Probing liquid-liquid phase transitions via fast and localized temperature stimuli — •Anatol Fritsch1, Matthäus Mittasch1, Andrés Diaz1, Frank Jülicher2, Anthony Hyman1, and Moritz Kreysing1 — 1MPI of Molecular Cell Biology and Genetics, Dresden — 2MPI for the Physics of Complex Systems, Dresden
Recent studies report membrane-less organelles (MLO) to show liquid-like behavior formed by phase transition of aqueous solutions. These organelles foster a dynamic, spatially separated platform for important biochemical reactions inside the cell. In C. elegans embryos MLOs called P granules segregate asymmetrically and play a key role in the specification of the germ cell fate. We want to shed light on the physical principles underlying this segregation process.
Since liquid-like organelles are formed by phase separation, they should respond to variations in their environment such as changes in pH, salt concentration or temperature. To study the kinetics of MLO phase transition we use temperature as a control parameter for defined changes between the mixed and demixed state. For fast and localized temperature control, we use a custom build IR-laser scanning microscopy setup combined with a Peltier controlled sample stage. Experiments on in vivo P granules and corresponding in vitro reconstituted systems show fast transition times and allow for the characterization of growth and melting kinetics of the phase separated domains. Furthermore, specific temperature patterns can be used to capture the thermodynamics of P granule segregation inside the embryo.