Presenter:
Pierre Sens, Ph.D.
Research Director - CNRS and Team leader - Institut Curie
Modelling membrane-bound cellular organelles with non-equilibrium dynamics.
Membrane-bound cellular organelles perform many essential functions, among which the sorting and biochemical maturation of cellular components. Organelles along the secretory and endocytic pathways are strongly out-of-equilibrium structures, which display large stochastic fluctuations of composition and shape resulting from inter-organelle exchange and enzymatic reactions. Understanding how the different molecular mechanisms controlling these processes are orchestrated to yield robust fluxes of matter and to direct particular components to particular locations within the cell is an outstanding problem of great interest for cell biologist, but also for physicists.
In this talk, I will discuss a conceptual model of organelle biogenesis and maintenance that include vesicular exchange (budding, transport, and fusion) and biochemical maturation, i.e. the change of identity of an organelle over time (early to late endosomes, cis to trans Golgi cisternae…). I will show how the non-equilibrium steady-state of an organelle or a network of organelles may be varied in a controlled manner by modifying a limited number of coarse-grained parameters (essentially, the budding, fusion and maturation rates) and discuss the relevance of these results for the structure of the endosomal network andGolgi apparatus.
ShortBio:
Pierre Sens is Directeur de Recherche at CNRS working at Institut Curie, in Paris. Pierre received his PhD from the University of Strasbourg (France) in 1996 in the field of soft condensed matter and complex fluids. He then moved to U.C. SantaBarbara for a couple of years, then to Institut Weizmann in Israel for a year, before coming back to France with the CNRS. Pierre is a theoretical physicist applying physical concepts to the study of biological systems, in particular to living cells. He investigates the active mechanics of cells, with a focus on cell motility and mechano-sensation. Pierre also studies cellular membranes, particularly the dynamics on intracellular membranes and the generation and maintenance of cellular organelles
