Abstract
Various aerolysin-like pore-forming proteins have been identified from bacteria to vertebrates. However, the mechanism of receptor recognition and/or pore formation of the eukaryotic members remains unknown. Here, we present the first crystal and electron microscopy structures of a vertebrate aerolysin-like protein from Danio rerio, termed Dln1, before and after pore formation. Each subunit of Dln1 dimer comprises a β-prism lectin module followed by an aerolysin module. Specific binding of the lectin module toward high-mannose glycans triggers drastic conformational changes of the aerolysin module in a pH-dependent manner, ultimately resulting in the formation of a membrane-bound octameric pore. Structural analyses combined with computational simulations and biochemical assays suggest a pore-forming process with an activation mechanism distinct from the previously characterized bacterial members. Moreover, Dln1 and its homologs are ubiquitously distributed in bony fishes and lamprey, suggesting a novel fish-specific defense molecule.
Original language | English (US) |
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Pages (from-to) | 235-248 |
Number of pages | 14 |
Journal | EMBO Reports |
Volume | 17 |
Issue number | 2 |
DOIs | |
State | Published - Feb 1 2016 |
Externally published | Yes |
Keywords
- crystal structure
- electron microscopy reconstruction
- high-mannose glycan
- pore-forming protein
- vertebrate
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Genetics