Phosphatidic acid features double membrane vesicle formation during Hepatitis C and SARS-CoV-2 infection

ABSTRACT: Double membrane vesicles (DMVs) are used as replication organelles by pathogenic RNA viruses such as hepatitis C virus (HCV) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Viral DMVs are morphologically analogous to DMVs formed during autophagy, and although the proteins required for DMV formation are extensively studied, the lipids driving their biogenesis are largely unknown. Here we show that production of the lipid phosphatidic acid (PA) by acylglycerolphosphate acyltransferase (AGPAT) 1 and 2 in the ER is important for DMV biogenesis in autophagy and viral replication. Using DMVs in HCV-replicating cells as model, we found that AGPATs are recruited to and critically contribute to viral replication in HCV and SARS-CoV-2 infected cells. AGPAT1/2 double knockout impaired HCV and SARS-CoV-2 induced DMV biogenesis as well as formation of autophagosomes. By using correlative light and electron microscopy, we observed the relocalisation of AGPAT proteins to viral DMVs. In addition, an intracellular PA sensor accumulated at DMV formation sites, consistent with elevated levels of PA in fractions of purified DMVs analyzed by lipidomics. Apart from AGPATs, PA is generated by alternative pathways via phosphotidylcholine (PC) and diacylglycerol (DAG). Pharmacological inhibition of these synthesis pathways also impaired HCV and SARS-CoV-2 replication. These data identify PA as an important lipid that is used in seemingly disparate biological processes, i.e. autophagy and replication organelle formation by diverse RNA viruses. In addition, our data argue that host-targeting therapy aiming at PA synthesis pathways might be suitable to control SARS-CoV-2 replication.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Hepatocyte, Liver

DISEASE(S): Hepatitis C

SUBMITTER: Frédéric FONTAINE  

LAB HEAD: Ralf Bartenschlager

PROVIDER: PXD029692 | Pride | 2022-01-24

REPOSITORIES: Pride