On the contrary, the absence of Syt1-C2B domains allow for a just nucleated fusion pore to collapse more easily, letting the system evolve towards pore resealing, and following the path of a kiss-and-run event. This result is in agreement with the hypothesis of flickering fusion pores between lipid membranes in the absence of proteins, proposed more than 20 years ago by Zimmerberg and collaborators. Here, we hypothesize that the Syt1-C2B domains equalize the energy landscape in the nucleation region (figure , dashed line in the pink zone)