Download MendeleyComplexin cross-links prefusion SNAREs into a zigzag array.
Kummel, D., Krishnakumar, S.S., Radoff, D.T., Li, F., Giraudo, C.G., Pincet, F., Rothman, J.E., Reinisch, K.M.(2011) Nat Struct Mol Biol 18: 927-933
- PubMed: 21785414
- DOI: https://doi.org/10.1038/nsmb.2101
- Primary Citation of Related Structures:
3RK2, 3RK3, 3RL0 - PubMed Abstract:
Complexin prevents SNAREs from releasing neurotransmitters until an action potential arrives at the synapse. To understand the mechanism for this inhibition, we determined the structure of complexin bound to a mimetic of a prefusion SNAREpin lacking the portion of the v-SNARE that zippers last to trigger fusion. The 'central helix' of complexin is anchored to one SNARE complex, while its 'accessory helix' extends away at ~45° and bridges to a second complex, occupying the vacant v-SNARE binding site to inhibit fusion. We expected the accessory helix to compete with the v-SNARE for t-SNARE binding but found instead that the interaction occurs intermolecularly. Thus, complexin organizes the SNAREs into a zigzag topology that, when interposed between the vesicle and plasma membranes, is incompatible with fusion.
Organizational Affiliation:
Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut, USA.
