Abstract
The zoonotic emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the ensuing coronavirus disease 2019 (COVID-19) pandemic have profoundly affected our society. The rapid spread and continuous evolution of new SARS-CoV-2 variants continue to threaten global public health. Recent scientific advances have dissected many of the molecular and cellular mechanisms involved in coronavirus infections, and large-scale screens have uncovered novel host-cell factors that are vitally important for the virus life cycle. In this Review, we provide an updated summary of the SARS-CoV-2 life cycle, gene function and virus–host interactions, including recent landmark findings on general aspects of coronavirus biology and newly discovered host factors necessary for virus replication.
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Acknowledgements
The authors thank all our colleagues in the field of coronaviruses, who have helped to increase our knowledge of this virus family since its discovery. Owing to the scope and focus of this manuscript, they have primarily focused on recent publications working with SARS-CoV-2; however, we appreciate that many of these insights are built on a strong foundation of research on previous coronaviruses during the past decades. Work in the authors’ laboratory was supported by the Swiss National Science Foundation (grants 310030B_201278 and NCCR ‘RNA & Disease’ grant 205601).
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S.S., A.K., G.T.B., R.M.L., J.N.K., E.A.M. and V.T. researched the data for the article. S.S., A.K., G.T.B., R.M.L., J.N.K. and V.T. wrote the manuscript. S.S., A.K., G.T.B. and R.M.L. prepared the figures, under the supervision of V.T. L.T. contributed to writing and revising the text.
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Nature Reviews Microbiology thanks Luis Enjuanes, who co-reviewed with Sonia Zuñiga; Timothy Sheahan, who co-reviewed with Meghan Diefenbacher; and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
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Glossary
- Cis-acting elements
-
RNA elements found in RNA viruses that regulate processes such as viral transcription, replication, packaging or expression of genes on the same RNA.
- Double-membrane vesicles
-
Virus-induced organelles that are delimited by two membrane bilayers and dedicated to replication or transcription of the viral RNA.
- Internal ribosomal entry sites
-
RNA elements that allow binding of ribosomes and initiation of translation in a cap-independent manner.
- Lipid droplets
-
Cellular lipid depositories that regulate lipid storage and metabolism.
- Liquid–liquid phase separation
-
A process that establishes two distinct phases from a homogeneous solution; in the context of macromolecules, it is often related to the formation of membrane-less condensates of proteins and RNA.
- Monocistronic
-
Refers to messenger RNA molecules that encode a single gene product.
- Polycistronic
-
Refers to mRNA molecules that encode more than one gene product.
- Viroporin
-
A viral protein with hydrophobic region that can assemble into ion channels or molecular pores on membranes.
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Steiner, S., Kratzel, A., Barut, G.T. et al. SARS-CoV-2 biology and host interactions. Nat Rev Microbiol 22, 206–225 (2024). https://doi.org/10.1038/s41579-023-01003-z
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DOI: https://doi.org/10.1038/s41579-023-01003-z