Signaling Pathway Reporter Screen with SARS-CoV-2 Proteins Identifies nsp5 as a Repressor of p53 Activity

Abstract

The dysregulation of host signaling pathways plays a critical role in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and viral pathogenesis. While a number of viral proteins that can block type I IFN signaling have been identified, a comprehensive analysis of SARS-CoV-2 proteins in the regulation of other signaling pathways that can be critical for viral infection and its pathophysiology is still lacking. Here, we screened the effect of 21 SARS-CoV-2 proteins on 10 different host signaling pathways, namely, Wnt, p53, TGFβ, c-Myc, Hypoxia, Hippo, AP-1, Notch, Oct4/Sox2, and NF-κB, using a luciferase reporter assay. As a result, we identified several SARS-CoV-2 proteins that could act as activators or inhibitors for distinct signaling pathways in the context of overexpression in HEK293T cells. We also provided evidence for p53 being an intrinsic host restriction factor of SARS-CoV-2. We found that the overexpression of p53 is capable of reducing virus production, while the main viral protease nsp5 can repress the transcriptional activity of p53, which depends on the protease function of nsp5. Taken together, our results provide a foundation for future studies, which can explore how the dysregulation of specific signaling pathways by SARS-CoV-2 proteins can control viral infection and pathogenesis.

A novel gene signature based on the hub genes of COVID-19 predicts the prognosis of idiopathic pulmonary fibrosis

“…The results of KEGG and GO pathway enrichment indicated that those genes were mostly enriched in DNA replication, immunomodulation, and energy metabolism. Increasing studies of COVID-19 patients showed that SARS-Cov-2 infects and replicates in endothelial cells in multiple organs, such as the heart, lung, kidney, and liver ( Dashtban et al, 2022 ; Giovannini et al, 2022 ; John et al, 2022 ; Kumar et al, 2022 ; Schold et al, 2022 ; Zheng et al, 2022 ). In addition, the enriched pathway p53 signaling was identified as a key pathway of genomic stability and cell cycle progression, it even plays a great part in the suppression of viral replication ( Kumar et al, 2022 ).…”

“…Increasing studies of COVID-19 patients showed that SARS-Cov-2 infects and replicates in endothelial cells in multiple organs, such as the heart, lung, kidney, and liver (Dashtban et al, 2022;Giovannini et al, 2022;John et al, 2022;Kumar et al, 2022;Schold et al, 2022;Zheng et al, 2022). In addition, the enriched pathway p53 signaling was identified as a key pathway of genomic stability and cell cycle progression, it even plays a great part in the suppression of viral replication (Kumar et al, 2022). Those augments further explained the genes we explored were hub genes Frontiers in Pharmacology frontiersin.org 10 involved in the pathological course of COVID-19.…”

Therapeutic potential of the MDM2 inhibitor Nutlin-3 in counteracting SARS-CoV-2 infection of the eye through p53 activation

“…Moreover, it was observed that knockout of TP53 gene promoted viral replication, and that, on the opposite, the expression of p53 served as antiviral cellular molecule able to downregulate SARS-CoV replication ( 5 ). More recently, another group, screening the impact of SARS-CoV-2 proteins in several signaling pathways involved in viral infection, has demonstrated that the viral protease nsp5 can functionally repress p53 by interfering with its transcriptional activity, and has suggested p53 as an “intrinsic host restriction factor for the virus” ( 6 ). Similarly to Ma-Lauer, they have also observed that the overexpression of p53 significantly reduced virus production, sustaining the hypothesis of a fundamental role of p53 in managing the cellular antiviral defenses.…”

Cell cycle block by p53 activation reduces SARS-CoV-2 release in infected alveolar basal epithelial A549-hACE2 cells

“…One of the targets of the virus that plays an important role both in the mechanisms of innate immunity and in the control of the cell cycle and other pathways that regulate cell replication, damage repair, apoptosis and metabolism is the p53 protein ( Cardozo and Hainaut, 2021 ; Ma-Lauer et al, 2016 ; Zauli et al, 2020 ; Harford et al, 2022 ; Kumar et al, 2022 ; Zauli et al, 2022 ). Indeed, the tumor suppressor p53 is a pleiotropic protein controlling cell homeostasis and cell response to stress events, deciding cell fate.…”

“…Indeed, the viral Papain-Like Proteases (PLPs) act directly on MDM2 and on RING finger and CHY zinc finger domain-containing protein 1 (RCHY1) the “core” ubiquitin ligases involved in p53 ubiquitination, promoting their stabilization, and forwarding p53 to the proteasome degradation ( Ma-Lauer et al, 2016 ; Yuan et al, 2015 ). Moreover, viral Non-Structural Protein 5 (NSP5) can interfere with p53 transcriptional activity, impacting the regulation of its target genes ( Kumar et al, 2022 ). Vice versa, overexpression of recombinant TP53 gene has shown some capacity to moderate SARS-CoV replication ( Ma-Lauer et al, 2016 ; Kumar et al, 2022 ).…”