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bioRxiv · 10.1101/2021.09.26.461873

Viroporin activity of SARS-CoV-2 Orf3a and Envelope protein impacts viral pathogenicity

Sarkar, M.·Etheimer, P.·Saha, S.
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Abstract

COVID-19 is caused by SARS-CoV-2 which has so far affected more than 500 million people worldwide and killed over 6 million as of 1st May, 2022. The approved emergency-use vaccines were lifesaving to such a devastating pandemic. Viroporins are important players of the life cycle of SARS-CoV-2 and are primary to its pathogenesis. We studied the two prominent viroporins of SARS-CoV-2 (i) Orf3a and (ii) Envelope (E) protein from a sequential and structural point of view. Orf3a is a cation selective viral ion channel which has been shown to disrupt the endosomal pathways. E protein is one of the most conserved proteins among the SARS-CoV proteome which affects the ERGIC related pathways. The aqueous medium through the viroporins mediates the non-selective translocation of cations, affecting ionic homeostasis in the host cellular compartments. This ionic imbalance could potentially lead to increased inflammatory response in the host cell. Our results shed light into the mechanism of viroporin action, which can be potentially leveraged for the development of antiviral therapeutics. Our results corroborate with previously published transcriptomic data from COVID-19 infected lung alveolar cells where inflammatory responses and molecular regulators directly impacted by ion channelling were upregulated.

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Sarkar, M., Etheimer, P., Saha, S.. 2021-09-26. Viroporin activity of SARS-CoV-2 Orf3a and Envelope protein impacts viral pathogenicity. https://doi.org/10.1101/2021.09.26.461873

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