Download MendeleyThe Full-Length Cell-Cell Fusogen Eff-1 is Monomeric and Upright on the Membrane.
Zeev-Ben-Mordehai, T., Vasishtan, D., Siebert, C.A., Grunewald, K.(2014) Nat Commun 5: 3912
- PubMed: 24867324
- DOI: https://doi.org/10.1038/ncomms4912
- Primary Citation of Related Structures:
4CYL - PubMed Abstract:
Fusogens are membrane proteins that remodel lipid bilayers to facilitate membrane merging. Although several fusogen ectodomain structures have been solved, structural information on full-length, natively membrane-anchored fusogens is scarce. Here we present the electron cryo microscopy three-dimensional reconstruction of the Caenorhabditis elegans epithelial fusion failure 1 (EFF-1) protein natively anchored in cell-derived membrane vesicles. This reveals a membrane protruding, asymmetric, elongated monomer. Flexible fitting of a protomer of the EFF-1 crystal structure, which is homologous to viral class-II fusion proteins, shows that EFF-1 has a hairpin monomeric conformation before fusion. These structural insights, when combined with our observations of membrane-merging intermediates between vesicles, enable us to propose a model for EFF-1 mediated fusion. This process, involving identical proteins on both membranes to be fused, follows a mechanism that shares features of SNARE-mediated fusion while using the structural building blocks of the unilaterally acting class-II viral fusion proteins.
Organizational Affiliation:
Oxford Particle Imaging Centre, Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK.
