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bioRxiv · 10.1101/2021.02.18.431684

Delivery of recombinant SARS-CoV-2 envelope protein into human cells

Hutchison, J. M.·Capone, R.·Luu, D. D.·Hadziselimovic, A.·Van Horn, W. D.·Sanders, C. R.
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Abstract

SARS-CoV-2 envelope protein (S2-E) is a conserved membrane protein that is essential to coronavirus assembly and budding. Here, we describe the recombinant expression and purification of S2-E into amphipol-class amphipathic polymer solutions. The physical properties of amphipols underpin their ability to solubilize and stabilize membrane proteins without disrupting membranes. Amphipol delivery of S2-E to pre-formed planar bilayers results in spontaneous membrane integration and formation of viroporin ion channels. Amphipol delivery of the S2-E protein to human cells results in membrane integration followed by retrograde trafficking to a location adjacent to the endoplasmic reticulum-to-Golgi intermediate compartment (ERGIC) and the Golgi, which are the sites of coronavirus replication. Delivery of S2-E to cells enables both chemical biological approaches for future studies of SARS-CoV-2 pathogenesis and development of "Trojan Horse" anti-viral therapies. This work also establishes a paradigm for amphipol-mediated delivery of membrane proteins to cells.

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Hutchison, J. M., Capone, R., Luu, D. D., Hadziselimovic, A., Van Horn, W. D., Sanders, C. R.. 2021-02-19. Delivery of recombinant SARS-CoV-2 envelope protein into human cells. https://doi.org/10.1101/2021.02.18.431684

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