SARS-CoV-2 nsp3-4 suffice to form a pore shaping replication organelles

Zimmermann, L.; Zhao, X.; Makroczyova, J.; Wachsmuth-Melm, M.; Prasad, V.; Bartenschlager, R.; Chlanda, P.

doi:10.1101/2022.10.21.513196

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bioRxiv · 10.1101/2022.10.21.513196

SARS-CoV-2 nsp3-4 suffice to form a pore shaping replication organelles

Zimmermann, L.·Zhao, X.·Makroczyova, J.·Wachsmuth-Melm, M.·Prasad, V.·Bartenschlager, R.·Chlanda, P.

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Abstract

Coronavirus replication is associated with the remodeling of cellular membranes resulting in the formation of double-membrane vesicles (DMVs). Recently, a pore spanning DMV was identified as a putative portal for viral RNA transcription and replication products providing a novel target for antiviral intervention. However, the exact components and the structure of the SARS-CoV-2 pore remain to be determined. Here, we investigate the structure of DMV pores by in situ cryo-electron tomography combined with subtomogram averaging. We reveal non-structural proteins (nsp) 3 and 4 as minimal components forming a DMV spanning pore and show that nsp3 Ubl1-Ubl2 domains are critical for inducing membrane curvature and DMV formation. Altogether, SARS-CoV-2 nsp3-4 has a dual role by driving the biogenesis of replication organelles and forming DMV-spanning replicopores. One-Sentence SummaryBiogenesis of SARS-CoV-2 replication organelles is driven by nsp3-4 constituting the double-membrane vesicle spanning pore.

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Zimmermann, L., Zhao, X., Makroczyova, J., Wachsmuth-Melm, M., Prasad, V., Bartenschlager, R., Chlanda, P.. 2022-10-21. SARS-CoV-2 nsp3-4 suffice to form a pore shaping replication organelles. https://doi.org/10.1101/2022.10.21.513196

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