Molecular elucidation of drug-induced abnormal assemblies of the Hepatitis B Virus capsid protein by solid-state NMR

Lecoq, L.; Brigandat, L.; Huber, R.; Fogeron, M.-L.; Callon, M.; Malaer, A.; Wang, S.; Dujardin, M.; Briday, M.; Wiegand, T.; Durantel, D.; Burdette, D.; Berke, J.-M.; Meier, B. H.; Nassal, M.; Bockmann, A.

doi:10.1101/2022.09.14.507909

bioRxiv · 10.1101/2022.09.14.507909

Molecular elucidation of drug-induced abnormal assemblies of the Hepatitis B Virus capsid protein by solid-state NMR

Lecoq, L.·Brigandat, L.·Huber, R.·Fogeron, M.-L.·Callon, M.·Malaer, A.·Wang, S.·Dujardin, M.·Briday, M.·Wiegand, T.·Durantel, D.·Burdette, D.·Berke, J.-M.·Meier, B. H.·Nassal, M.·Bockmann, A.

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Abstract

Hepatitis B virus (HBV) capsid assembly modulators (CAMs) represent a new class of anti-HBV antivirals. CAMs disturb proper nucleocapsid assembly, by inducing formation of either aberrant assemblies (CAM-A) or of apparently normal but genome-less empty capsids (CAM-E). Classical structural approaches have revealed the CAM binding sites on the capsid protein (Cp), but conformational information on the CAM-induced off-path aberrant assemblies is lacking. We show that solid-state NMR can provide such information, including for wild-type full-length Cp183, and we find that in these assemblies, the asymmetric unit comprises a single Cp molecule rather than the four quasi-equivalent conformers typical for the icosahedral T=4 symmetry of the normal HBV capsids. Furthermore, while in contrast to truncated Cp149, full-length Cp183 assemblies appear, on the mesoscopic level, unaffected by CAM-A, NMR reveals that on the molecular level, Cp183 assemblies are equally aberrant. Finally, we use a eukaryotic cell-free system to reveal how CAMs modulate capsid-RNA interactions and capsid phosphorylation. Our results establish a structural view on assembly modulation of the HBV capsid, and they provide a rationale for recently observed differences between in-cell versus in vitro capsid assembly modulation.

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Lecoq, L., Brigandat, L., Huber, R., Fogeron, M.-L., Callon, M., Malaer, A., Wang, S., Dujardin, M., Briday, M., Wiegand, T., Durantel, D., Burdette, D., Berke, J.-M., Meier, B. H., Nassal, M., Bockmann, A.. 2022-09-15. Molecular elucidation of drug-induced abnormal assemblies of the Hepatitis B Virus capsid protein by solid-state NMR. https://doi.org/10.1101/2022.09.14.507909

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