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Mis-localized mitochondrial ribosomes guide ceramide-dependent mitophagy for inducing cell death via alterations of the bioenergetics and metabolism

ABSTRACT: In this work, we set out experiments to determine the mechanisms that regulate mitochondrial trafficking of p17/PERMIT-CerS1 complex in response to Drp1 activation to induce mitophagy and cellular consequences of this process altering mitochondrial metabolism in cultured cells in situ and genetic mice models in vivo. The data revealed that mislocalized mitochondrial ribosomes on the outer membrane due to Drp1-mediated fission are recognized by p17/PERMIT for CerS1 localization leading to ceramide-dependent mitophagy in response to oxidative stress by the generation of nitric oxide species (NOS). This process then leads to mitochondrial dysfunction resulting in decreased malate/fumarate/aspartate exhaustion, which is restored and prevented by molecular and genetic ablation of p17/PERMIT, LC3, Drp1, and Parkin in cancer cells or patient-derived 2D-organoids or mice brains in response to SoSe or ceramide analog drug, LCL768.

ORGANISM(S): Homo sapiens

PROVIDER: GSE182781 | GEO | 2021/12/01

REPOSITORIES: GEO

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Project description:This study aims to investigate the role and mechanism of DEK in asthmatic airway inflammation and in regulating PTEN-induced putative kinase 1 (PINK1)-Parkin mediated mitophagy, NLRP3 (NOD-like receptor family pyrin domain containing 3) inflammasome activation, and apoptosis. We found that recombinant DEK protein (rmDEK) promoted eosinophils recruitment, mitochondrial fragmentation, and outer membrane 20 (TOM20) and LC3 co-localization representing mitophagosomes in bronchoalveolar lavage fluid (BALF) in house dust mite (HDM) induced-asthma. rmDEK also reduced co-localization of mitochondrial fusion protein mitofusin1 (MFN1) and mitochondria, and the protein level of manganese superoxide dismutase (MnSOD), enhanced microtubule-associated protein1 light chain 3 (LC3) and voltage-dependent anion channels (VDAC) co-localization which also represent the mitophagosomes in airway epithelial cells, furthermore, increased dynamin-related protein 1 (DRP1) expression, PINK1-Parkin-mediated mitophagy, NLRP3 inflammasome activation, and apoptosis. In the DEK knockout mice, HDM induced asthmatic airway inflammation, MnSOD, PINK1-Parkin protein level, Parkin mediated mitophagy characterized by LC3 and Parkin co-localization in the airways, ROS generation, NLRP3 inflammation and apoptosis were fully reversed. Similar effects of rmDEK were also observed in the BEAS-2B cells, which were rescued by the autophagy inhibitor 3-MA. Moreover, DEK silencing diminished the Parkin, LC3, DRP1 translocation to mitochondria; as well as mitochondrial ROS; TOM20 and mitochondrial DNA mediated mitochondrial oxidative damage. ChIP-sequence analysis showed that DEK was enriched on the AAA domain-containing protein 3A (ATAD3A) promoter and could positively regulate ATAD3A expression. Additionally, ATAD3A was highly expressed in HDM-induced asthma models. Furthermore, ATAD3A interacted with DRP1, and knockdown of ATAD3A could down-regulate DRP1 and mitochondrial oxidative damage. Conclusively, DEK deficiency alleviates airway inflammation in asthma by down-regulating PINK1-Parkin mitophagy, NLRP3 inflammasome activation, and apoptosis. The mechanism may be through the DEK/ATAD3A/DRP1 signaling axis. Our findings may provide new potential therapeutic targets for asthma treatment.

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Mis-localized mitochondrial ribosomes guide ceramide-dependent mitophagy for inducing cell death via alterations of the bioenergetics and metabolism

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