SARS-CoV-2 hijacks p38β/MAPK11 to promote virus replication

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the coronavirus disease 2019 (COVID-19) pandemic, drastically modifiesinfected cells to optimize virus replication. One such modificationis the activation of the host p38 mitogen-activated protein kinase (MAPK) pathway, which plays a major role in inflammatorycytokine production, a hallmark of severe COVID-19. We previously demonstrated that inhibition of p38/MAPK activity in SARS-CoV-2-infected cells reduced both cytokine production and viral replication. Here, we combined quantitative genetic screening, genomics, proteomics, and phosphoproteomics to better understand mechanisms underlying the dependence of SARS-CoV-2 on the p38 pathway. We found that p38β is a critical host factor for SARS-CoV-2 replication in multiple relevant cell lines and that it functions at a step after viral mRNA expression. We identifiedputative host and viral p38β substrates in the context of SARS-CoV-2 infection and found that most host substrates have intrinsic antiviral activities. Taken together, this study reveals a unique proviral function for p38β and supports exploring p38β inhibitor development as a strategy toward creating a new class of COVID-19 therapies.