Epsin N-terminal homology domains bind on opposite sides of two SNAREs

• Published in: Proceedings of the National Academy of Sciences - PNAS 2011-07, Vol.108 (30), p.12277-12282
• Main Authors: Wang, Jing, Gossing, Michael, Fang, Pengfei, Zimmermann, Jana, Li, Xu, von Mollard, Gabriele Fischer, Niu, Liwen, Teng, Maikun
• Format: Article
• Language: English
• Subjects: Adaptor Proteins, Vesicular Transport - chemistry; Adaptor Proteins, Vesicular Transport - genetics; Adaptor Proteins, Vesicular Transport - metabolism; Amino Acid Sequence; Animals; Binding sites; Biological Sciences; Budding; Conserved Sequence; Crystal structure; Crystallography, X-Ray; Crystals; Freight; Humans; in vivo studies; Mammals; membrane fusion; Membrane Fusion - physiology; Membranes; Mice; Models, Molecular; Molecular Sequence Data; Mutagenesis, Site-Directed; Organelles; P branes; Protein Interaction Domains and Motifs; Proteins; Qb-SNARE Proteins - chemistry; Qb-SNARE Proteins - genetics; Qb-SNARE Proteins - metabolism; Recombinant Proteins - chemistry; Recombinant Proteins - genetics; Recombinant Proteins - metabolism; Saccharomyces cerevisiae Proteins - chemistry; Saccharomyces cerevisiae Proteins - genetics; Saccharomyces cerevisiae Proteins - metabolism; sequence homology; Sequence Homology, Amino Acid; SNARE proteins; SNARE Proteins - chemistry; SNARE Proteins - genetics; SNARE Proteins - metabolism; Two-Hybrid System Techniques; Yeast; Yeasts
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.1013101108

SNARE proteins are crucial for membrane fusion in vesicular transport. To ensure efficient and accurate fusion, SNAREs need to be sorted into different budding vesicles. This process is usually regulated by specific recognition between SNAREs and their adaptor proteins. How different pairs of SNAREs and adaptors achieve their recognition is unclear. Here, we report the recognition between yeast SNARE Vti1p and its adaptor Ent3p derived from three crystal structures. Surprisingly, this yeast pair Vti1p/Ent3p interacts through a distinct binding site compared to their homologues vti1b/epsinR in mammals. An opposite surface on Vti1p_Habc domain binds to a conserved area on the epsin N-terminal homology (ENTH) domain of Ent3p. Two-hybrid, in vitro pull-down and in vivo experiments indicate this binding interface is important for correct localization of Vti1p in the cell. This previously undescribed discovery that a cargo and adaptor pair uses different binding sites across species suggests the diversity of SNARE-adaptor recognition in vesicular transport.