Kiss-and-run

Rizzoli SO, Jahn R (2007) Kiss-and-run, collapse and readUy retrievable vesicles. Traffic 8 1137-1144... 

However, an alternative pathway that bypasses clathrin-mediated endocytosis and EEs appears to be available as well. This model of endocytosis known as kiss and run or its variant kiss and stay have attracted increasing interest in recent years [74] (Fig. 9-9B). Kiss and run has been directly demonstrated with dense-core granules in neuroendocrine cells [84, 85], and this model would explain some observations that are not readily accommodated by the classical pathway. The kiss and run model proposes that neurotransmitters are released by a transient fusion pore, rather than by a complete fusion with integration of the synaptic vesicle components into the plasma membrane. Synaptic membrane proteins never lose their association and the vesicle reforms when the pore closes. As a result, the empty vesicle can be refilled and reused without going through clathrin-mediated endocytosis and sorting in the EEs. 

Direct demonstrations of the kiss and run model in mammalian synapses have remained elusive [73], but there is sufficient evidence to suggest that there may be up... 

In addition to functioning as Ca2+-sensors for vesicle exocytosis, synaptotag-mins may be involved in vesicle endocytosis, particularly the decision between kiss-and-run versus full exocytosis. Such a role would be economical in linking fusion-pore opening (which is triggered by Ca2+-binding to synaptotagmin) to fusion-pore expansion or contraction, but the precise mechanisms involved have not yet been explored. 

Harata NC, Aravanis AM, Tsien,R (2006) Kiss-and-run and full-collapse fusion as modes of exo-endocytosis in neurosecretion. J Neurochem 97 1546-70 Hosaka M, Stidhof TC (1998) Synapsins I and II are ATP-binding proteins with differential Ca2+ regulation. J Biol Chem 273 1425-9 Jahn R, Lang T, Stidhof TC (2003) Membrane fusion. Cell 112 519-33... 

Exocytosis of synaptic vesicles or of regulated secretory granules results in incorporation of membrane into the plasma membrane. For maintaining the cell surface area constant, homeostatic mechanisms are required that assure a rapid and efficient re-intemalization of the incorporated vesicle membranes. Different types of vesicle recycling pathways are discussed for synapses (Figure 5), including fast retrieval of the vesicle at the site of exocytosis, called kiss-and-run, a slower clathrin-dependent pathway, and other clathrin-independent retrieval pathways (Royle and... 

According to the classical view, synaptic vesicles completely flatten during exo-cytosis, which is followed by retrieval of the membrane components by clathrin-dependent endocytosis. Evidence for direct retrieval (kiss-and-run) was provided... 

In the kiss-and-run mode exocytosis and endocytosis are directly coupled to each other, while in the case of classical complete vesicle fusion, exocytosis and slow clathrin-mediated endocytosis are timely and spatially separated. However, it appears that also in the latter case exocytosis and endocytosis occur coordinated, as both are stimulated by an increase of the cytoplasmic calcium concentration. It has been shown that after calcium entry the enzyme phospho-inositol-5 kinase Iy, which is enriched in the synapse, catalyzes the synthesis of phosphatidylinos-itol (4,5)-bisphosphate and that this mechanism is important for synaptic vesicle trafficking (Di Paolo et al. 2004). As many proteins involved in clathrin-mediated endocytosis are recruited to the plasma membrane by binding to phosphatidylinosi-tol (4,5)-bisphosphate (e.g., amphiphysin, dynamin, epsin, AP-180, and AP-2) it is attractive to speculate that elevated levels of calcium mediate the recruitment of en-docytic proteins to the plasma membrane by this mechanism. The increased level of phosphatidylinositol (4,5)-bisphosphate could be in part degraded by synaptojanin that thereby initiates the disassembly of the clathrin coat. Hence, calcium-induced transient increases in the level of phosphatidylinositol (4,5)-bisphosphate appear to play a central role for coupling exocytosis to clathrin-mediated endocytosis. In addition, it has been demonstrated that calcium also leads to the dephosphorylation of endocytic proteins as amphiphysin, dynamin, and synaptojanin, which in vitro is important for efficient coat assembly (Cousin and Robinson 2001). 

Fernandez JM, Neher E, Gomperts BD (1984) Capacitance measurements reveal stepwise fusion events in degranulating mast cells. Nature 312 453-5 Fesce R, Grohovaz F, Valtorta F, Meldolesi J (1994) Neurotransmider release fusion or kiss-and-run Trends Cell Biol 4 1 4... 

Chen, X., Wang, L., Zhou, Y., Zheng, L. H., and Zhou, Z. (2005). Kiss-and-run glutamate secretion in cultured and freshly isolated rat hippocampal astrocytes.. Neurosci. 25, 9236—9243. 

Fesce, R., Grohovaz, F., Valtorta, F., and Meldolesi, J. (1994). Neurotransmitter release Fusion or kiss-and-run Trends Cell Biol. 4, 1-4. 

Elhamdani A, Azizi F, Artalejo CR. 2006. Double patch clamp reveals that transient fusion (kiss-and-run) is a major mechanism of secretion in calf adrenal chromaffin cells High calcium shifts the mechanism from kiss-and-run to complete fusion. J Neurosci 26 3030-3036. 

Wightman RM, Haynes CL. Synaptic vesicles really do kiss and run. Nat. Neurosci. 2004 7 321-322. 

Fesce R, Grohovaz F, Valtorta F, Meldolesi J. Neurotransmitter release fusion or kiss-and-run Trends Cell Biol. 1994 4 1-4. 

Harata NC, Choi S, Pyle JL, Aravanis AM, Tsien RW. Frequency-dependent kinetics and prevalence of kiss-and-run and reuse at hippocampal synapses studied with novel quenching methods. Neuron 2006 49 243-256. 

The concept of synaptic vesicle recycling was conclusively established in the early 1970s (Holtzman et al., 1971 Cec-carelli et al., 1973 Heuser and Reese, 1973), and the role of clathrin-mediated endocytosis in the recycling of synaptic vesicles is now well established. A model of endocytosis referred to as kiss-and-run has attracted considerable interest (Ceccarelli et al., 1973 Fesce et al., 1994). In this model, vesicles release neurotransmitter via a transient fusion pore. Newly reformed vesicles may then stay in place, be reloaded, and undergo a new round of exocytosis or may de-dock and allow other vesicles to take their place. 

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