Our research is focused on the dynamics of cells, from the motion of bio-molecules such as proteins and nucleic acids to that of larger structures like membranes to that of cells themselves. We are interested in different types of molecular movements: diffusion in solution and in membranes, active transport along microtubules or across nuclear pore complexes, insertion in membranes, binding with other molecules and conformational changes. We mainly use fluorescence fluctuation spectroscopy and single particle tracking to detect and quantify these different types of motion. We complement these dynamics studies by structural studies done with neutron & x-ray scattering. An important aspect of our investigations is that they range from studies done in reconstituted systems to studies done in live cells. We currently have five separate areas of research.