Elimination of rNMPs from mitochondrial DNA has no effect on its stability.

ABSTRACT: Ribonucleotides (rNMPs) incorporated in the nuclear genome are a well-established threat to genome stability and can result in DNA strand breaks when not removed in a timely manner. However, the presence of a certain level of rNMPs is tolerated in mitochondrial DNA (mtDNA) although aberrant mtDNA rNMP content has been identified in disease models. We investigated the effect of incorporated rNMPs on mtDNA stability over the mouse life span and found that the mtDNA rNMP content increased during early life. The rNMP content of mtDNA varied greatly across different tissues and was defined by the rNTP/dNTP ratio of the tissue. Accordingly, mtDNA rNMPs were nearly absent in SAMHD1^-/- mice that have increased dNTP pools. The near absence of rNMPs did not, however, appreci

SUBMITTER: Wanrooij PH 

PROVIDER: S-EPMC7322039 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature