How do secretory cells release their cargo so fast ?

How do proteins organized within a membrane produce the speed and precision of cellular secretion? Answering this question requires observing the molecular machinery while measuring what it does. Using suspended lipid membranes, a silicon-chip platform that connects single-molecule measurements with the docking, fusion, and cargo release of individual secretory vesicles. Built from synthetic or cell-derived membranes,  the platform preserves lipid asymmetry and protein mobility while enabling protein counting and dynamic tracking within a functional membrane.
In this talk, I will present how this technology allows us to dissect the relationship between molecular organization and calcium-triggered membrane fusion. By systematically varying membrane composition and regulatory proteins, we can examine how the assembly and coordination of the fusion machinery shape secretion. I will discuss evidence for shared organizational principles underlying rapid release from synaptic and dense-core vesicles, linking controlled reconstitution to the complexity of native secretory systems. Together, these studies address a fundamental question in membrane biology: how do protein number, spatial organization, and lipid environment cooperate to make a membrane ready to fuse ?