Live cell imaging shows that the cAMP-sensor Epac2, a target of major antidiabetic drugs, is central to fusion pore control during insulin granule exocytosis.
During neurotransmitter release, calcium-induced membrane insertion of the C2B domain of Synaptotagmin re-orients the bound SNARE complex which dilates the fusion pore in a mechanical lever action.
A few SNARE complexes suffice to fuse membranes, but many more are needed to dilate the nascent fusion pore by molecular crowding for efficient neurotransmitter or hormone release during exocytosis.
Genetic, proteomic, and structural analyses provide insight into the role of Brl1 during nuclear pore complex biogenesis, suggesting a function in the fusion of outer and inner nuclear membranes.
The SNAP-25 linker acts as a functional component of SNARE complexes, initially facilitating SNARE interactions and later promoting fusion triggering and pore evolution by local membrane contacts.
Rigorous assays of membrane fusion show that a distinct tethering step is required for lumenal compartment mixing in a manner that extends beyond simply increasing the amount of total trans-SNARE complex.
Madhurima Dhara, Maria Mantero Martinez ... Dieter Bruns
Naturally-occurring v-SNARE TMD variants differentially regulate fusion pore dynamics and cooperate with phospholipids in supporting membrane curvature at the fusion pore neck.
An in vitro reconstitution assay reveals stoichiometric levels of the short form of Opa1 work together with the long form of Opa1 to mediate efficient and fast membrane pore opening.
