Molecular architecture of coronavirus double-membrane vesicle pore complex.
Huang, Y., Wang, T., Zhong, L., Zhang, W., Zhang, Y., Yu, X., Yuan, S., Ni, T.(2024) Nature 633: 224-231
- PubMed: 39143215 
- DOI: https://doi.org/10.1038/s41586-024-07817-y
- Primary Citation of Related Structures:  
8YAX, 8YB5, 8YB7 - PubMed Abstract: 
Coronaviruses remodel the intracellular host membranes during replication, forming double-membrane vesicles (DMVs) to accommodate viral RNA synthesis and modifications 1,2 . SARS-CoV-2 non-structural protein 3 (nsp3) and nsp4 are the minimal viral components required to induce DMV formation and to form a double-membrane-spanning pore, essential for the transport of newly synthesized viral RNAs 3-5 . The mechanism of DMV pore complex formation remains unknown. Here we describe the molecular architecture of the SARS-CoV-2 nsp3-nsp4 pore complex, as resolved by cryogenic electron tomography and subtomogram averaging in isolated DMVs. The structures uncover an unexpected stoichiometry and topology of the nsp3-nsp4 pore complex comprising 12 copies each of nsp3 and nsp4, organized in 4 concentric stacking hexamer rings, mimicking a miniature nuclear pore complex. The transmembrane domains are interdigitated to create a high local curvature at the double-membrane junction, coupling double-membrane reorganization with pore formation. The ectodomains form extensive contacts in a pseudo-12-fold symmetry, belting the pore complex from the intermembrane space. A central positively charged ring of arginine residues coordinates the putative RNA translocation, essential for virus replication. Our work establishes a framework for understanding DMV pore formation and RNA translocation, providing a structural basis for the development of new antiviral strategies to combat coronavirus infection.
Organizational Affiliation: 
School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China.