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

• DOI: 10.1073/pnas.1916851117
• Publication Date: 2020-06-09T00:36:15Z
• Authors: Paulina H. Wanrooij; Phong Tran; Liam J. Thompson; Gustavo Carvalho; Sushma Sharma; Katrin Kreisel; Clara Navarrete; Anna-Lena Feldberg; Danielle L. Watt; Anna Karin Nilsson; Martin K. M. Engq...; Anders R. Clausen; Andrei Chabes
• Keywords: Nuclear DNA; Life span

Ribonucleotides (rNMPs) incorporated in the nuclear genome are a well-established threat to stability and can result DNA strand breaks when not removed timely manner. However, presence of certain level rNMPs is tolerated mitochondrial (mtDNA) although aberrant mtDNA rNMP content has been identified disease models. We investigated effect on over mouse life span found that increased during early life. The varied greatly across different tissues was defined by rNTP/dNTP ratio tissue. Accordingly, were nearly absent SAMHD1 −/− mice have dNTP pools. near absence did not, however, appreciably affect copy number or levels molecules with deletions aged animals end their span. physiological load therefore does contribute progressive loss quality occurs as age.