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bioRxiv · 10.1101/2022.03.04.483074

SARS-CoV-2 triggers Golgi fragmentation via downregulation of GRASP55 to facilitate viral trafficking

Abstract

The COVID-19 pandemic is caused by SARS-CoV-2, an enveloped RNA virus. Despite extensive investigation, the molecular mechanisms for its assembly and secretion remain largely elusive. Here, we show that SARS-CoV-2 infection induces global alterations of the host endomembrane system, including dramatic Golgi fragmentation. SARS-CoV-2 virions are enriched in the fragmented Golgi. Disrupting Golgi function with small molecules strongly inhibits viral infection. Significantly, SARS-CoV-2 infection down-regulates GRASP55 but up-regulates TGN46 protein levels. Surprisingly, GRASP55 expression reduces both viral secretion and spike number on each virion, while GRASP55 depletion displays opposite effects. In contrast, TGN46 depletion only inhibits viral secretion without affecting spike incorporation into virions. TGN46 depletion and GRASP55 expression additively inhibit viral secretion, indicating that they act at different stages. Taken together, we show that SARS-CoV-2 alters Golgi structure and function to control viral assembly and secretion, highlighting the Golgi as a potential therapeutic target for blocking SARS-CoV-2 infection.

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Zhang, J., Kennedy, A., Xing, L., Bui, S., Reid, W., Joppich, J., Ahat, E., Rose, M., Tang, Q., Tai, A. W., Wang, Y.. 2022-03-07. SARS-CoV-2 triggers Golgi fragmentation via downregulation of GRASP55 to facilitate viral trafficking. https://doi.org/10.1101/2022.03.04.483074

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