Τίτλος:
Proteasome dysfunction induces excessive proteome instability and loss of mitostasis that can be mitigated by enhancing mitochondrial fusion or autophagy
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
The ubiquitin-proteasome pathway (UPP) is central to proteostasis network (PN) functionality and proteome quality control. Yet, the functional implication of the UPP in tissue homeodynamics at the whole organism level and its potential cross-talk with other proteostatic or mitostatic modules are not well understood. We show here that knock down (KD) of proteasome subunits in Drosophila flies, induced, for most subunits, developmental lethality. Ubiquitous or tissue specific proteasome dysfunction triggered systemic proteome instability and activation of PN modules, including macroautophagy/autophagy, molecular chaperones and the antioxidant cncC (the fly ortholog of NFE2L2/Nrf2) pathway. Also, proteasome KD increased genomic instability, altered metabolic pathways and severely disrupted mitochondrial functionality, triggering a cncC-dependent upregulation of mitostatic genes and enhanced rates of mitophagy. Whereas, overexpression of key regulators of antioxidant responses (e.g., cncC or foxo) could not suppress the deleterious effects of proteasome dysfunction; these were alleviated in both larvae and adult flies by modulating mitochondrial dynamics towards increased fusion or by enhancing autophagy. Our findings reveal the extensive functional wiring of genomic, proteostatic and mitostatic modules in higher metazoans. Also, they support the notion that age-related increase of proteotoxic stress due to decreased UPP activity deregulates all aspects of cellular functionality being thus a driving force for most age-related diseases. Abbreviations: ALP: autophagy-lysosome pathway; ARE: antioxidant response element; Atg8a: autophagy-related 8a; ATPsynβ: ATP synthase, β subunit; C-L: caspase-like proteasomal activity; cncC: cap-n-collar isoform-C; CT-L: chymotrypsin-like proteasomal activity; Drp1: dynamin related protein 1; ER: endoplasmic reticulum; foxo: forkhead box, sub-group O; GLU: glucose; GFP: green fluorescent protein; GLY: glycogen; Hsf: heat shock factor; Hsp: Heat shock protein; Keap1: kelch-like ECH-associated protein 1; Marf: mitochondrial assembly regulatory factor; NFE2L2/Nrf2: nuclear factor, erythroid 2 like 2; Opa1: optic atrophy 1; PN: proteostasis network; RNAi: RNA interference; ROS: reactive oxygen species; ref(2)P: refractory to sigma P; SQSTM1: sequestosome 1; SdhA: succinate dehydrogenase, subunit A; T-L: trypsin-like proteasomal activity; TREH: trehalose; UAS: upstream activation sequence; Ub: ubiquitin; UPR: unfolded protein response; UPP: ubiquitin-proteasome pathway. © 2019, © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.
Συγγραφείς:
Tsakiri, E.N.
Gumeni, S.
Vougas, K.
Pendin, D.
Papassideri, I.
Daga, A.
Gorgoulis, V.
Juhász, G.
Scorrano, L.
Trougakos, I.P.
Εκδότης:
Taylor and Francis Inc.
Λέξεις-κλειδιά:
antioxidant; cap n collar isoform C; heat shock protein 70; proteasome; reactive oxygen metabolite; sequestosome 1; transcription factor Nrf2; unclassified drug; Atg8a protein, Drosophila; Drosophila protein; proteasome; proteome, antioxidant responsive element; Article; autophagy; cell viability; cellular, subcellular and molecular biological phenomena and functions; controlled study; diet restriction; DNA damage; Drosophila; enzyme activity; genomic instability; immunohistochemistry; larva; larvistatic activity; lysosome; mitochondrial dynamics; mitochondrial fusion; mitochondrial membrane potential; mitochondrial respiration; mitophagy; nonhuman; oxygen consumption; protein expression level; protein homeostasis; proteomics; respiratory chain; aging; animal; autophagy; Drosophila melanogaster; genetics; growth, development and aging; metabolism; mitochondrial dynamics; mitochondrion; physiology; protein degradation; transgenic animal, Aging; Animals; Animals, Genetically Modified; Autophagy; Drosophila melanogaster; Drosophila Proteins; Larva; Mitochondria; Mitochondrial Dynamics; Proteasome Endopeptidase Complex; Proteolysis; Proteome; Proteostasis
DOI:
10.1080/15548627.2019.1596477
