Colloquium Natural and Life Sciences - Milena Bertolotti

Nanoscale analytic tools and redox sensors to study B lymphocytes

The B cell antigen receptor (BCR) is pivotal in B lymphocytes physiology. However, the molecular mechanisms of its activation and signaling are still not completely understood. A crucial issue is whether and how the BCR and its interactors are functionally compartmentalized at nanometer distances on the cellular membrane. This is addressed using nanoscale analytic tools, such as the proximity ligation assay (PLA), whose advantages and prospective development will be highlighted. Furthermore, BCR signaling output is affected by reactive oxygen species (ROS) in a co-stimulatory way, but ROS fluxes have never been systematically studied, mainly because of their short-lived nature. To overcome this problem and to reach close proximity measurements, fluorescent sensor proteins, which are able to detect local ROS production inside the cell, were generated. In the talk there will be a specific focus on these redox sensors, in order to discuss also potential not-immunological applications.