The highly multidisciplinary Biophotonics team develops fluorescence-based imaging techniques and innovative probes, in order to apply them for solving key questions related to the molecular and cellular functions and interactions of viral and epigenetic proteins with their nucleic acid targets. The physicists and engineers of the team have implemented and developed home-made microscopy set-ups, which are regularly upgraded and optimized for new applications and projects. The team implemented in 2003 one of the first two-photon FLIM/FCS microscopes in France. Later, the team developed a high resolution 3D dSTORM/PALM microscope and a STED microscope with cw laser. In order to track and image UCNPs, an anti-Stokes wide-field for SPT and an anti-Stokes luminescence lifetime confocal microscope were developed. More recently, a spectral PAINT (sPAINT), a light sheet single molecule microscope and a single molecule UV microscope were developed. These instruments are accessible to the community through their integration into the platform PIQ-QuESt (IBISA).