+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Positively charged amino acids at the SNAP-25 C terminus determine fusion rates, fusion pore properties, and energetics of tight SNARE complex zippering

, : Positively charged amino acids at the SNAP-25 C terminus determine fusion rates, fusion pore properties, and energetics of tight SNARE complex zippering. Journal of Neuroscience 35(7): 3230-3239

SNAP-25 is a Q-SNARE protein mediating exocytosis of neurosecretory vesicles including chromaffin granules. Previous results with a SNAP-25 construct lacking the nine C terminal residues (SNAP-25Δ9) showed changed fusion pore properties (Fang et al., 2008), suggesting a model for fusion pore mechanics that couple C terminal zipping of the SNARE complex to the opening of the fusion pore. The deleted fragment contains the positively charged residues R198 and K201, adjacent to layers 7 and 8 of the SNARE complex. To determine how fusion pore conductance and dynamics depend on these residues, single exocytotic events in bovine chromaffin cells expressing R198Q, R198E, K201Q, or K201E mutants were investigated by carbon fiber amperometry and cell-attached patch capacitance measurements. Coarse grain molecular dynamics simulations revealed spontaneous transitions between a loose and tightly zippered state at the SNARE complex C terminus. The SNAP-25 K201Q mutant showed no changes compared with SNAP-25 wild-type. However, K201E, R198Q, and R198E displayed reduced release frequencies, slower release kinetics, and prolonged fusion pore duration that were correlated with reduced probability to engage in the tightly zippered state. The results show that the positively charged amino acids at the SNAP-25 C terminus promote tight SNARE complex zippering and are required for high release frequency and rapid release in individual fusion events.


PMID: 25698757

DOI: 10.1523/JNEUROSCI.2905-14.2015

Other references

Aurich, G.; Bigl, S.; Grahlow, W.D.; Handrick, W.; Hudemann, H.; Köditz, H.; Krumpel, J.; Mitschke, I.; Mochmann, H.; Ocklitz, H.W.; Schneeweiss, B.; Wiersbitzky, S., 1981: Recommendations for the use of antiseptics on juvenile mucous membranes. Zeitschrift für Arztliche Fortbildung 75(10): 469-470

Vyssoulis, G.P.; Karpanou, E.A.; Kyvelou, S-Maria.G.; Adamopoulos, D.N.; Deligeorgis, A.D.; Spanos, P.G.; Pietri, P.G.; Cokkinos, D.F.; Stefanadis, C.I., 2007: Nocturnal blood pressure fall and metabolic syndrome score in hypertensive patients. Data relating dipping status to metabolic syndrome (MS) scores are not available. The purpose of this study is to investigate any possible association of different dipping patterns to MS scores in untreated patients with essential hypertension. Th...

Jarosińska, D.; Horvat, M.; Sällsten, G.; Mazzolai, B.; Dabkowska, B.; Prokopowicz, A.; Biesiada, M.; Barregård, L., 2008: Urinary mercury and biomarkers of early renal dysfunction in environmentally and occupationally exposed adults: a three-country study. We conducted a cross-sectional study in Sweden, Italy and Poland to assess environmental and occupational exposure to mercury from chloralkali (CA) plants and the potential association with biomarkers of early renal dysfunction. Questionnaire data...

Martinez-Flores,A.; Corrales-Garcia,J.J.; Espinosa-Solares,T.; Garcia-Gatica,P.G.; Villanueva-Verduzco,C., 2008: Postharvest changes in the edible mushroom huitlacoche Corda. Huitlacoche (<i>Ustilago maydis</i> (D.C.) Corda) has been an important food in the diet of the inhabitants of the Central-Southern region of Mexico since pre-Columbian times. Recently, its acceptance has increased all around the world...

Lindfors, C.; Katz, A.; Selander, L.; Johansen, J.E.; Marconi, G.; Schalling, M.; Hökfelt, T.; Berggren, P-Olof.; Zaitsev, S.; Nilsson, I.A.K., 2015: Glucose intolerance and pancreatic β-cell dysfunction in the anorectic anx/anx mouse. Inflammation and impaired mitochondrial oxidative phosphorylation are considered key players in the development of several metabolic disorders, including diabetes. We have previously shown inflammation and mitochondrial dysfunction in the hypothal...

Lazzarotto, T.; Lanari, M., 2012: Why is cytomegalovirus the most frequent cause of congenital infection?. Expert Review of Anti-Infective Therapy 9(10): 841-843

Gorren, A.C.F.; Werner, E.R.; Schmidt, K.; Mayer, B., 1998: Electrochemistry of pterin cofactors and antagonists of nitric oxide synthase. Nitric Oxide 2(5): 308

Bradley, C., 2004: "Hospitable" hospitals. Nursing Management 31(6): 25-25

Jones, PT., 1991: Peregrines at Symonds Yat 1991. Gloucestershire Bird Report, 86-87 No. 29

Sokolov B.I.; Chichuev Y.A., 1980: Concentration of ethanol in blood and urine depending on storage period. Sudebno-Meditsinskaya Ekspertiza 23(1): 38-40