A stagewise response to mitochondrial dysfunction in mitochondrial DNA maintenance disorders

Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved..

Mitochondrial DNA (mtDNA) deletions which clonally expand in skeletal muscle of patients with mtDNA maintenance disorders, impair mitochondrial oxidative phosphorylation dysfunction. Previously we have shown that these mtDNA deletions arise and accumulate in perinuclear mitochondria causing localised mitochondrial dysfunction before spreading through the muscle fibre. We believe that mito-nuclear signalling is a key contributor in the accumulation and spread of mtDNA deletions, and that knowledge of how muscle fibres respond to mitochondrial dysfunction is key to our understanding of disease mechanisms. To understand the contribution of mito-nuclear signalling to the spread of mitochondrial dysfunction, we use imaging mass cytometry. We characterise the levels of mitochondrial Oxidative Phosphorylation proteins alongside a mitochondrial mass marker, in a cohort of patients with mtDNA maintenance disorders. Our expanded panel included protein markers of key signalling pathways, allowing us to investigate cellular responses to different combinations of oxidative phosphorylation dysfunction and ragged red fibres. We find combined Complex I and IV deficiency to be most common. Interestingly, in fibres deficient for one or more complexes, the remaining complexes are often upregulated beyond the increase of mitochondrial mass typically observed in ragged red fibres. We further find that oxidative phosphorylation deficient fibres exhibit an increase in the abundance of proteins involved in proteostasis, e.g. HSP60 and LONP1, and regulation of mitochondrial metabolism (including oxidative phosphorylation and proteolysis, e.g. PHB1). Our analysis suggests that the cellular response to mitochondrial dysfunction changes depending on the combination of deficient oxidative phosphorylation complexes in each fibre.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:1870

Enthalten in:

Biochimica et biophysica acta. Molecular basis of disease - 1870(2024), 5 vom: 21. März, Seite 167131

Sprache:

Englisch

Beteiligte Personen:

Vincent, Amy E [VerfasserIn]
Chen, Chun [VerfasserIn]
Gomes, Tiago Bernardino [VerfasserIn]
Di Leo, Valeria [VerfasserIn]
Laalo, Tuomas [VerfasserIn]
Pabis, Kamil [VerfasserIn]
Capaldi, Rodrick [VerfasserIn]
Marusich, Michael F [VerfasserIn]
McDonald, David [VerfasserIn]
Filby, Andrew [VerfasserIn]
Fuller, Andrew [VerfasserIn]
Lehmann Urban, Diana [VerfasserIn]
Zierz, Stephan [VerfasserIn]
Deschauer, Marcus [VerfasserIn]
Turnbull, Doug [VerfasserIn]
Reeve, Amy K [VerfasserIn]
Lawless, Conor [VerfasserIn]

Links:

Volltext

Themen:

Cell signalling
Journal Article
Mitochondrial DNA deletion
Mitochondrial disease
Myopathy
OXPHOS

Anmerkungen:

Date Revised 05.04.2024

published: Print-Electronic

Citation Status Publisher

doi:

10.1016/j.bbadis.2024.167131

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM370109813