The story of cell secretion: Events leading to the discovery of the 'porosome' - The universal secretory machinery in cells

Abstract

Cell secretion has come of age, and a century old quest has been elegantly solved. We have come a long way since earlier observations of what appeared to be 'fibrillar regions' at the cell plasma membrane, and electrophysiological studies suggesting the presence of 'fusion pores' at the cell plasma membrane where secretion occurs. Finally, the fusion pore or 'porosome' has been discovered, and its morphology and dynamics determined at nm resolution and in real time in live secretory cells. The porosome has been isolated, its composition determined and it has been both structurally and functionally reconstituted in artificial lipid membrane. The discovery of the porosome as the universal secretory machinery in cells and the discovery of the molecular mechanism of vesicular content expulsion during cell secretion have finally enabled a clear understanding of this important cellular process. This review outlines the fascinating and exciting journey leading to the discovery of the porosome, ultimately solving one of the most difficult, significant, and fundamental cellular process -cell secretion.