Research interests

My research interests cover a wide range of topics both in physics (statistical physics, confined polymers, out-of-equilibrium physics) and biophysics (chromatin remodeling, epigenetics, molecular motors, cancer physics, nuclear pore complex). Most of these studies are based on single molecule experiments and modeling. The specificity here is to focus on a physical mechanism at stake in a biological phenomenon (e.g. cargo confinement in nuclear pore complex) and to investigate this process by means of controlled in vitro or ex vivo experiments.

Translocation of biomolecules through nanopores

We have established a method to follow individual biomolecules as DNA, RNA or proteins as they translocate through artificial nanopores. In our case the nanoporous membranes are unexpensive track etch membranes that were originally designed for water filtration. These polycarbonates membranes are sputtered with a thin layer of gold in order to produce Zero-Mode waveguides which are small metallic structures at the exit of pore. These structures strongly enhance and localize the fluorescence emission of the biomolecules when they reach the exit of the nanopore. The presence of high densities of nanopores in these membranes natively induce a very high parallelization of the measurements.

We have used this method to measure the free ernergy landscape of translocation for long biomolecules inside nanopores. We have shown that the deGennes-Brochard suction model was an effective description of the hydrodynamical injection of flexible polymers. This model was also extended to the use of electrical field as a driving parameter and also to semi-flexible polymers.

Nuclear pore complex structure and dynamics

The nuclear pore complex is the only gateway between the cell nucleus and the cytoplasm. It is composed of a large number of components (30 proteins present in multiple copies) including unstructured proteins (FG-nups). The mechanisms of its selectivity and directionnality are still heavily debated. We have used optical super resolution microscopy (dSTORM) to reveal the plasticity of this pore during a developmental process. We have also shown and characterized the formation of square lattice organized nanodomains of nuclear pores during this process.