Molecular mechanism of calcium-triggered vesicle fusion

A Chemical Controller of SNARE-Driven Membrane Fusion That Primes Vesicles for Ca2+-Triggered Millisecond Exocytosis

“…44,45 When 500 µM Ca 2+ was injected 14% of the SRB-containing vesicles opened fusion pore in 10 s. When the cumulative content mixing event was fitted to a double-exponential first-order kinetics time constants for fast and slow component were 474 ms and 2.55 s, respectively, which are comparable values to those of a previous report (Table S1). 9 Consistent with previous studies, 9,31,44,45 10 µM Ca 2+ did not trigger content mixing of the vesicle pairs arranged through scheme C (Fig. 4D).…”

“…9,31,44,45 SV-vesicles containing SRB were added to the sample chamber and incubated with T-vesicles immobilized on a cover glass at 25 °C for 1 min. After free SV-vesicles were washed out, the interacting vesicle pairs were further incubated at 25 °C for 40 min (Fig.…”

“…3,8,17,23,24 Reconstitution of the primed state, which is ready to respond to Ca 2+ influx through exocytosis in a millisecond timescale, is thought to help clarify the molecular mechanism underlying the remarkable speed and synchrony of neuroexocytosis. 1,8,9,22,25–28 Until now, however, studies have not been successful in reconstituting the primed vesicles that exhibit every aspect of RRP in speed, synchrony, and reactivity to physiological Ca 2+ concentrations.…”

Statistical Mechanics of Viral Entry

“…Here, we formulate a predictive statisticalmechanical framework that attempts to capture -quantitatively -the common principles by which enveloped viruses overcome high kinetic barriers to infect host cells on a timescale of minutes. The theory establishes a direct connection with a series of recent single-particle assays capable of measuring the kinetics of viral infection [10,11] and neuronal communication [12,13]. The theory results in analytical expressions for the key quantities that have become accessible due to these experiments: the dwell time distributions for the stages of fusion as a function of an external signal.…”

Single-molecule FRET study of SNARE-mediated membrane fusion

“…Two major ways of utilizing single-molecule FRET (smFRET) technique have been applied on SNARE-mediated membrane fusion through monitoring SNARE protein interactions [6,7,8,9,10] or fusion of lipid molecules [11,12,13,14,15,16]. Most recent application of the smFRET approach has been the use of labeled content [17] and the combination of the lipid marker and the labeled content [18]. …”