Dysregulation of intracellular redox homeostasis by the SARS-CoV-2 ORF6 protein

© 2023. BioMed Central Ltd., part of Springer Nature..

SARS-CoV-2 has evolved several strategies to overcome host cell defenses by inducing cell injury to favour its replication. Many viruses have been reported to modulate the intracellular redox balance, affecting the Nuclear factor erythroid 2-Related Factor 2 (NRF2) signaling pathway. Although antioxidant modulation by SARS-CoV-2 infection has already been described, the viral factors involved in modulating the NRF2 pathway are still elusive. Given the antagonistic activity of ORF6 on several cellular pathways, we investigated the role of the viral protein towards NRF2-mediated antioxidant response. The ectopic expression of the wt-ORF6 protein negatively impacts redox cell homeostasis, leading to an increase in ROS production, along with a decrease in NRF2 protein and its downstream controlled genes. Moreover, when investigating the Δ61 mutant, previously described as an inactive nucleopore proteins binding mutant, we prove that the oxidative stress induced by ORF6 is substantially related to its C-terminal domain, speculating that ORF6 mechanism of action is associated with the inhibition of nuclear mRNA export processes. In addition, activation by phosphorylation of the serine residue at position 40 of NRF2 is increased in the cytoplasm of wt-ORF6-expressing cells, supporting the presence of an altered redox state, although NRF2 nuclear translocation is hindered by the viral protein to fully antagonize the cell response. Furthermore, wt-ORF6 leads to phosphorylation of a stress-activated serine/threonine protein kinase, p38 MAPK, suggesting a role of the viral protein in regulating p38 activation. These findings strengthen the important role of oxidative stress in the pathogenesis of SARS-CoV-2 and identify ORF6 as an important viral accessory protein hypothetically involved in modulating the antioxidant response during viral infection.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:20

Enthalten in:

Virology journal - 20(2023), 1 vom: 18. Okt., Seite 239

Sprache:

Englisch

Beteiligte Personen:

De Angelis, Marta [VerfasserIn]
Anichini, Gabriele [VerfasserIn]
Palamara, Anna Teresa [VerfasserIn]
Nencioni, Lucia [VerfasserIn]
Gori Savellini, Gianni [VerfasserIn]

Links:

Volltext

Themen:

452VLY9402
Antagonistic proteins
Antioxidants
Journal Article
NF-E2-Related Factor 2
NRF2
ORF6
ORF6 protein, SARS-CoV-2
Oxidative stress
Research Support, Non-U.S. Gov't
SARS-CoV-2
Serine
Viral Proteins

Anmerkungen:

Date Completed 30.10.2023

Date Revised 22.11.2023

published: Electronic

Citation Status MEDLINE

doi:

10.1186/s12985-023-02208-7

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM363458832