Gap junctions are intercellular channels present in almost all epithelia and in many other specialized tissues. The correct function and formation of gap junctions are involved in diseases such as hypertension, deafness or cataracts. Gap junctions are formed by pairs of hexameric half-channels called connexons, which coaxially dock to connect two adjacent cells, assuring communication, signalling and adhesion between cells. Junctional microdomains are known to be form by thousands of closely packed connexon pairs. Even if the function as intercellular channels of gap junctions is widely studied, the forces supported by connexon pairs and the biophysical mechanism of microdomain formation are still unknown. The overall goal of this project is to determine the biophysical mechanisms of the adhesion strength of gap junctions. The proposed research will make use of state of the art biochemistry methods to purify and reconstitute connexons from eye lens fiber cells into raw membranes extracts. These will be combined with high end biophysical tools, atomic force microscopy and biomembrane force probe, to directly measure the binding forces between connexon pairs and to determine the kinetics and biophysical mechanisms of the aggregation and assembly of gap junctions. The expected outcomes of the proposed research will provide the first direct measure, at single and multiple molecule levels, of the adhesion strength of gap junctions explaining its underlying biophysical mechanisms. The interest of the project covers disciplines such as biophysics, molecular biology and nanotechnology.