Access
To read this article in full you may need to log in, make a payment or gain access through a site license (see right).
Article
Nature Structural & Molecular Biology 14, 890–896 (1 October 2007) | doi:10.1038/nsmb1310
Energetics and dynamics of SNAREpin folding across lipid bilayers
&
Abstract
Membrane fusion occurs when SNAREpins fold up between lipid bilayers. How much energy is generated during SNAREpin folding and how this energy is coupled to the fusion of apposing membranes is unknown. We have used a surface forces apparatus to determine the energetics and dynamics of SNAREpin formation and characterize the different intermediate structures sampled by cognate SNAREs in the course of their assembly. The interaction energy–versus–distance profiles of assembling SNAREpins reveal that SNARE motifs begin to interact when the membranes are 8 nm apart. Even after very close approach of the bilayers (|[sim]|2–4 nm), the SNAREpins remain partly unstructured in their membrane-proximal region. The energy stabilizing a single SNAREpin in this configuration (35 kBT) corresponds closely with the energy needed to fuse outer but not inner leaflets (hemifusion) of pure lipid bilayers (40–50 kBT).
To read this article in full you may need to log in, make a payment or gain access through a site license (see right).
