SARS-CoV-2 Membrane Protein Induces MARCHF1/GPX4-Mediated Ferroptosis by Promoting Lipid Accumulation

Area of Science:

• Virology
• Cellular Metabolism
• Pathology

Background:

• The SARS-CoV-2 membrane protein (M) is crucial for virus assembly and linked to organ damage and metabolic issues.
• Understanding M protein's role in host cell processes like ferroptosis and lipid accumulation is vital for COVID-19 treatment strategies.

Purpose of the Study:

• To investigate the mechanisms by which the SARS-CoV-2 M protein induces host ferroptosis and lipid accumulation.
• To identify key host factors and pathways involved in M-mediated cellular damage.
• To explore potential therapeutic targets within these pathways.

Main Methods:

• Assessing cellular sensitivity to ferroptosis upon M protein expression.
• Analyzing the role of perilipin-2 and SREBP1 in M-induced lipid accumulation.
• Evaluating the effects of xanthohumol, a DGAT inhibitor, on lipid levels and ferroptosis.
• Investigating the involvement of TIM23 and TOMM20 in M-induced mitochondrial dysfunction.
• Examining the interaction between M protein and GPX4, and its ubiquitylation by MARCH1.

Main Results:

• M protein expression increases cellular susceptibility to ferroptosis.
• Perilipin-2 and SREBP1 are key mediators of M-induced lipid accumulation.
• Xanthohumol reduces lipid accumulation and counteracts M-induced ferroptosis.
• M protein contributes to mitochondrial dysfunction via TIM23 and TOMM20.
• M protein interacts with GPX4, leading to its degradation by MARCH1, a process involving M's R72 residue.
• Inhibiting lipid synthesis mitigates mitochondrial dysfunction, suggesting a lipid-ferroptosis pathway crosstalk.

Conclusions:

• The SARS-CoV-2 M protein promotes ferroptosis and lipid accumulation through specific host factors and pathways.
• M protein induces mitochondrial dysfunction, exacerbating cellular damage.
• The interaction between M protein and GPX4, mediated by MARCH1, is a critical axis in SARS-CoV-2 pathogenesis.
• Targeting the M-GPX4-MARCH1 axis or lipid metabolism presents a potential therapeutic strategy for COVID-19.