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1.N.8.  The Tension-induced Vesicle Fusion (TiVF) Family

Two distinct vesicle fusion pathways have been observed that depend on the initial vesicle tension (Gao et al. 2008). In pathway I, at low membrane tension, a flattened adhesion zone is formed between the vesicles, and one vesicle subsequently ruptures in this contact zone to form a hemifusion state. This state is unstable and eventually opens a pore to complete the fusion process. In pathway II, at higher tension, a stalk is formed during the fusion process that is then transformed by transmembrane pore formation into a fusion pore. Whereas pathway II resembles stalk pathways as observed in other simulation studies, fusion pathway I, which does not involve stalk formation. A statistical analysis of the various processes showed that fusion is the dominant pathway for releasing the tension of the vesicles. The functional dependence of the observed fusion time on membrane tension implied that the fusion process is completed by overcoming two energy barriers with scales of 13kBT and 11kBT. The fusion pore radius as a function of time has also been extracted from simulations, and provides a quantitative measure of the fusion dynamics (Gao et al. 2008).

References associated with 1.N.8 family:

Gao, L., R. Lipowsky, and J. Shillcock. (2008). Tension-induced vesicle fusion: pathways and pore dynamics. Soft Matter 4: 1208-1214. 32907263