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bioRxiv · 10.1101/2021.06.01.446555

Endomembrane systems are reorganized by ORF3a and Membrane (M) of SARS-CoV-2

Lee, Y.-B.·Jung, M.·Kim, J.·Kang, M.-G.·Kwak, C.·Kim, J.-S.·Mun, J.-Y.·Rhee, H.-W.
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Abstract

The endomembrane reticulum (ER) is largely reorganized by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 ORF3a and membrane (M) protein expression affects ER-derived structures including cubic membrane and double membrane vesicles in coronavirus-infected cells; however, the molecular mechanisms underlying ER remodeling remain unclear. We introduced a "plug and playable" proximity labeling tool (TurboID-GBP) for interactome mapping of GFP-tagged SARS-CoV-2 ORF3a and M proteins. Through mass spectrometric identification of the biotinylated lysine residue (K+226 Da) on the viral proteins using Spot-TurboID workflow, 117 and 191 proteins were robustly determined as ORF3a and M interactomes, respectively, and many, including RNF5 (E3 ubiquitin ligase), overlap with the mitochondrial-associated membrane (MAM) proteome. RNF5 expression was correlated to ORF3a ubiquitination. MAM formation and secreted proteome profiles were largely affected by ORF3a expression. Thus, SARS-CoV-2 may utilize MAM as a viral assembly site, suggesting novel anti-viral treatment strategies for blocking viral replication in host cells. HighlightsO_LISARS-CoV-2 proteins ORF3a and M alter endoplasmic reticulum proteome profile C_LIO_LIORF3a affects mitochondrial-associated membrane formation C_LIO_LISARS-CoV-2 may utilize mitochondrial-associated membrane as viral assembly site C_LIO_LIORF3a and M interactome proteins may serve as targets for COVID-19 treatment C_LI eTOC BlurbER remodelling by SARS-CoV-2 ORF3a and M protein

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Lee, Y.-B., Jung, M., Kim, J., Kang, M.-G., Kwak, C., Kim, J.-S., Mun, J.-Y., Rhee, H.-W.. 2021-06-01. Endomembrane systems are reorganized by ORF3a and Membrane (M) of SARS-CoV-2. https://doi.org/10.1101/2021.06.01.446555

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