Download MendeleyStructural insights into the activation mechanism of antimicrobial GBP1.
Weismehl, M., Chu, X., Kutsch, M., Lauterjung, P., Herrmann, C., Kudryashev, M., Daumke, O.(2024) EMBO J 43: 615-636
- PubMed: 38267655
- DOI: https://doi.org/10.1038/s44318-023-00023-y
- Primary Citation of Related Structures:
8R1A - PubMed Abstract:
The dynamin-related human guanylate-binding protein 1 (GBP1) mediates host defenses against microbial pathogens. Upon GTP binding and hydrolysis, auto-inhibited GBP1 monomers dimerize and assemble into soluble and membrane-bound oligomers, which are crucial for innate immune responses. How higher-order GBP1 oligomers are built from dimers, and how assembly is coordinated with nucleotide-dependent conformational changes, has remained elusive. Here, we present cryo-electron microscopy-based structural data of soluble and membrane-bound GBP1 oligomers, which show that GBP1 assembles in an outstretched dimeric conformation. We identify a surface-exposed helix in the large GTPase domain that contributes to the oligomerization interface, and we probe its nucleotide- and dimerization-dependent movements that facilitate the formation of an antimicrobial protein coat on a gram-negative bacterial pathogen. Our results reveal a sophisticated activation mechanism for GBP1, in which nucleotide-dependent structural changes coordinate dimerization, oligomerization, and membrane binding to allow encapsulation of pathogens within an antimicrobial protein coat.
Organizational Affiliation:
Structural Biology, Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), 13125, Berlin, Germany.
