Dataset Information

Mitochondrial Interactome: A Focus on Antiviral Signaling Pathways.

ABSTRACT: In the last years, proteomics has represented a valuable approach to elucidate key aspects in the regulation of type I/III interferons (IFNs) and autophagy, two main processes involved in the response to viral infection, to unveil the molecular strategies that viruses have evolved to counteract these processes. Besides their main metabolic roles, mitochondria are well recognized as pivotal organelles in controlling signaling pathways essential to restrain viral infections. In particular, a major role in antiviral defense is played by mitochondrial antiviral signaling (MAVS) protein, an adaptor protein that coordinates the activation of IFN inducing pathways and autophagy at the mitochondrial level. Here, we provide an overview of how mass spectrometry-based studies of protein-protein interactions and post-translational modifications (PTMs) have fostered our understanding of the molecular mechanisms that control the mitochondria-mediated antiviral immunity.

SUBMITTER: Refolo G

PROVIDER: S-EPMC7033419 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Mitochondrial Interactome: A Focus on Antiviral Signaling Pathways.

Refolo Giulia G Vescovo Tiziana T Piacentini Mauro M Fimia Gian Maria GM Ciccosanti Fabiola F

Frontiers in cell and developmental biology 20200214

In the last years, proteomics has represented a valuable approach to elucidate key aspects in the regulation of type I/III interferons (IFNs) and autophagy, two main processes involved in the response to viral infection, to unveil the molecular strategies that viruses have evolved to counteract these processes. Besides their main metabolic roles, mitochondria are well recognized as pivotal organelles in controlling signaling pathways essential to restrain viral infections. In particular, a major ...[more]

PMID: 32117959

Similar Datasets

Project description:The mitochondrial and nuclear genomes contribute to mitochondrial function, and when mitochondrial function is compromised, mitochondrial retrograde signaling alters nuclear gene expression. We performed gene expression profiling of engineered cells that had mitochondria containing a disease-associated mutation that causes mitochondrial dysfunction. By generating networks of transcription factors that targeted these genes, the authors revealed putative mitochondrial retrograde signaling pathways. One such pathway involved retinoic acid receptor alpha (RXRA), the mRNA for which was reduced in the mutant cells. Network analysis and experiments in cells suggested that mitochondrial dysfunction caused by the mutation initiated a positive feedback loop that aggravated mitochondrial dysfunction: Reduced RXRA abundance further compromised expression of genes encoding products involved in mitochondrial function and translation. This gene-transcription factor mapping-network approach may reveal targets for therapeutic intervention of diseases associated with mitochondrial dysfunction. To investigate retrograde signaling pathways induced by the mitochondrial dysfunction caused by the mt3243 mutation, we generated the three types of cybrid cells using a mitochondria-mediated transformation method. Cells lacking mtDNA (rho0) were fused with mtDNAs with the mt3243 mutation isolated from platelets of a diabetic patient with sensorineural hearing loss. We then isolated three types of cybrid cells: W cells had wild-type mtDNA (3243A homoplasmy), H cells had both the mutant and wild-type mtDNA (3243A/G heteroplasmy) with 70% of the mtDNA containing 3243G, and M cells with only mutant mtDNA (3243G homoplasmy). Gene expression profiles of cybrid cells were generated using Illumina HumanHT-12-v3-BeadChip (Illumina, San Diego, CA), which includes 49,896 probes corresponding to 25,202 annotated genes. According to the Illumina protocols, three biological triplicates of each type of cybrid cells were analyzed. Total RNA (500ng) was isolated from cybrid cells using RNeasy Mini Kit (Qiagen, GmbH, Germany). RNA integrity number (RIN) was in the range of RIN = 9.2 and 10 when measured with an Agilent 2100 Bioanalyzer. RNA was reversely transcribed and amplified using IlluminaTotalPrep RNA amplification kit (Ambion, Austin, TX). In vitro transcription was then carried out to prepare cRNA. The cRNAs were hybridized to the array and then labeled with Cy3-streptavidin (Amersham Bioscience, Little Chalfont, UK). The fluorescent signal on the array was measured with a BeadStation 500 System (Illumina, San Diego, CA).

Project description:UnlabelledMitochondrial dysfunction is a pathogenic feature of nonalcoholic steatohepatitis (NASH). NASH complicates hepatotropic viral disease. The mitochondrial antiviral signaling protein (MAVS) is the adapter of helicase receptors involved in sensing double-stranded RNA (dsRNA). We hypothesized that impaired MAVS function may contribute to insufficient antiviral response and liver damage in steatohepatitis. We identified reduced MAVS protein levels and increased MAVS association with the proteasome subunit alpha type 7 (PSMA7) in livers from mice given a methionine-choline-deficient (MCD) diet. Decreased association of MAVS with mitochondria and increased cytosolic cytochrome c indicated mitochondrial damage in steatohepatitis. In vivo administration of the synthetic dsRNA polyinosinic:polycytidylic acid [poly(I:C)], but not lipopolysaccharide or cytidine-phosphate-guanosine-rich DNA, resulted in impaired induction of type I interferons (IFNs) and proinflammatory cytokines in steatohepatitis. Consistent with a defect in helicase receptor-induced signaling, there was loss of poly(I:C)-induced translocation of MAVS to the cytosol and decreased IFN regulatory factor 3 phosphorylation. Caspases 1 and 8, both of which cleave MAVS, were increased in MCD diet-fed mice. At baseline, steatohepatitis was associated with increased serum alanine aminotransferase (ALT), apoptosis and caspase 3 activation compared with controls. In contrast to apoptosis in controls, necrosis was induced by poly(I:C) stimulation in steatohepatitis. Hepatocyte necrosis was indicated by elevated serum high-mobility group box protein-1 and ALT and was correlated with increased expression of receptor-interacting protein 3 (RIP3), a master regulator of necrosis. Increased expression of MAVS, PSMA7, and RIP3 messenger RNA was also present in human NASH livers.ConclusionOur novel findings suggest that mitochondrial damage in steatohepatitis extends to MAVS, an adapter of helicase receptors, resulting in inefficient type I IFN and inflammatory cytokine response but increased hepatocyte necrosis and RIP3 induction in response to a dsRNA viral challenge. These mechanisms may contribute to progressive liver damage and impaired viral clearance in NASH.

Project description:Background & aimsUnlike other hepatitis viruses that have infected primates for millions of years, hepatitis A virus (HAV) likely entered human populations only 10-12 thousand years ago after jumping from a rodent host. The phylogeny of modern hepatoviruses that infect rodents and bats suggest that multiple similar host shifts have occurred in the past. The factors determining such shifts are unknown, but the capacity to overcome innate antiviral responses in a foreign species is likely key.MethodsWe assessed the capacity of diverse hepatovirus 3ABC proteases to cleave mitochondrial antiviral signaling protein (MAVS) and disrupt antiviral signaling in HEK293 and human hepatocyte-derived cell lines. We also applied maximum-likelihood and Bayesian algorithms to identify sites of diversifying selection in MAVS orthologs from 75 chiropteran, rodent and primate species.Results3ABC proteases from bat, but not rodent hepatoviruses efficiently cleaved human MAVS at Glu463/Gly464, disrupting virus activation of the interferon-β promoter, whereas human HAV 3ABC cleaved at Gln427/Val428. In contrast, MAVS orthologs from rodents and bats were resistant to cleavage by 3ABC proteases of cognate hepatoviruses and in several cases human HAV. A search for diversifying selection among MAVS orthologs from all 3 orders revealed 90 of ∼540 residues to be under positive selection, including residues in chiropteran MAVS that align with the site of cleavage of human MAVS by bat 3ABC proteases.Conclusions3ABC protease cleavage of MAVS is a conserved attribute of hepatoviruses, acting broadly across different mammalian species and associated with evidence of diversifying selection at cleavage sites in rodent and bat MAVS orthologs. The capacity of hepatoviruses to disrupt MAVS-mediated innate immune responses has shaped evolution of both hepatoviruses and their hosts, and facilitates cross-species transmission of hepatitis A.Lay summaryHepatitis A virus, a common cause of acute hepatitis globally, is likely to have evolved from a virus that jumped from a rodent species to humans within the last 10-12 thousand years. Here we show that distantly related hepatoviruses, that infect bats and rodents today, express proteases that disrupt innate antiviral responses in human cells. This conserved attribute of hepatoviruses may have contributed to that ancient host species shift.

Dataset Information

Mitochondrial Interactome: A Focus on Antiviral Signaling Pathways.

Publications

Mitochondrial Interactome: A Focus on Antiviral Signaling Pathways.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets