title: Discovery of the Porosome: revealing the molecular mechanism of secretion and membrane fusion in cells.
abstract: Secretion and membrane fusion are fundamental cellular processes involved in the physiology of health and disease. Studies within the past decade reveal the molecular mechanism of secretion and membrane fusion in cells. Studies reveal that membrane-bound secretory vesicles dock and fuse at porosomes, which are specialized plasma membrane structures. Swelling of secretory vesicles result in a build-up of intravesicular pressure, which allows expulsion of vesicular contents. The discovery of the porosome, its isolation, its structure and dynamics at nm resolution and in real time, its biochemical composition and functional reconstitution, are discussed. The molecular mechanism of secretory vesicle fusion at the base of porosomes, and vesicle swelling, have been resolved. With these findings a new understanding of cell secretion has emerged and confirmed by a number of laboratories.
authors.affiliation: Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201, USA. bjena@med.wayne.edu
authors.forename: B P
authors.initials: BP
authors.lastname: Jena
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism / Q000502:physiology*; D003600:Cytosol / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D008055:Lipids; D008081:Liposomes / Q000378:metabolism; D008561:Membrane Fusion; D008565:Membrane Proteins / Q000378:metabolism; D018625:Microscopy, Atomic Force; D008854:Microscopy, Electron; D008954:Models, Biological; D015388:Organelles / Q000502:physiology*; D050766:Qb-SNARE Proteins; D050767:Qc-SNARE Proteins; D050600:SNARE Proteins; D022142:Secretory Vesicles / Q000502:physiology*; D013329:Structure-Activity Relationship; D013997:Time Factors; D033921:Vesicular Transport Proteins
chemical_list: D002352:Carrier Proteins; D008055:Lipids; D008081:Liposomes; D008565:Membrane Proteins; D050766:Qb-SNARE Proteins; D050767:Qc-SNARE Proteins; C100493:SNAP23 protein, human; D050600:SNARE Proteins; D033921:Vesicular Transport Proteins