Ultrasensitive deletion detection links mitochondrial DNA replication, disease, and aging

Background Acquired human mitochondrial genome (mtDNA) deletions are symptoms and drivers of focal mitochondrial respiratory deficiency, a pathological hallmark of aging and late-onset mitochondrial disease. Results To decipher connections between these processes, we create LostArc, an ultrasensitive method for quantifying deletions in circular mtDNA molecules. LostArc reveals 35 million deletions (~ 470,000 unique spans) in skeletal muscle from 22 individuals with and 19 individuals without pathogenic variants in POLG. This nuclear gene encodes the catalytic subunit of replicative mitochondrial DNA polymerase γ. Ablation, the deleted mtDNA fraction, suffices to explain skeletal muscle phenotypes of aging and POLG-derived disease. Unsupervised bioinformatic analyses reveal distinct age- and disease-correlated deletion patterns. Conclusions These patterns implicate replication by DNA polymerase γ as the deletion driver and suggest little purifying selection against mtDNA deletions by mitophagy in postmitotic muscle fibers. Observed deletion patterns are best modeled as mtDNA deletions initiated by replication fork stalling during strand displacement mtDNA synthesis..

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:21

Enthalten in:

Genome biology - 21(2020), 1 vom: 17. Sept.

Sprache:

Englisch

Beteiligte Personen:

Lujan, Scott A. [VerfasserIn]
Longley, Matthew J. [VerfasserIn]
Humble, Margaret H. [VerfasserIn]
Lavender, Christopher A. [VerfasserIn]
Burkholder, Adam [VerfasserIn]
Blakely, Emma L. [VerfasserIn]
Alston, Charlotte L. [VerfasserIn]
Gorman, Grainne S. [VerfasserIn]
Turnbull, Doug M. [VerfasserIn]
McFarland, Robert [VerfasserIn]
Taylor, Robert W. [VerfasserIn]
Kunkel, Thomas A. [VerfasserIn]
Copeland, William C. [VerfasserIn]

Links:

Volltext [kostenfrei]

BKL:

42.13 / Molekularbiologie / Molekularbiologie

42.20 / Genetik / Genetik

Anmerkungen:

© The Author(s) 2020

doi:

10.1186/s13059-020-02138-5

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

OLC2119511969