The Fate of Oxidative Strand Breaks in Mitochondrial DNA.

ABSTRACT: Mitochondrial DNA (mtDNA) is particularly vulnerable to somatic mutagenesis. Potential mechanisms include DNA polymerase γ (POLG) errors and the effects of mutagens, such as reactive oxygen species. Here, we studied the effects of transient hydrogen peroxide (H₂O₂ pulse) on mtDNA integrity in cultured HEK 293 cells, applying Southern blotting, ultra-deep short-read and long-read sequencing. In wild-type cells, 30 min after the H₂O₂ pulse, linear mtDNA fragments appear, representing double-strand breaks (DSB) with ends characterized by short GC stretches. Intact supercoiled mtDNA species reappear within 2-6 h after treatment and are almost completely recovered after 24 h. BrdU incorporation is lower in H₂O₂-treated cells comp

SUBMITTER: Trombly G 

PROVIDER: S-EPMC10215735 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature