Journal Article

Exposure to environmental radionuclides alters mitochondrial DNA maintenance in a wild rodent

Kesäniemi Jenni, Moutinho, Ana Filipa, Watts, Phillip C, Mousseau, Timothy A, Tukalenko Eugene, Lavrinienko Anton, Møller, Anders Pape, Mappes Tapio

2020

Overview

Mitochondria are sensitive to oxidative stress, including that derived from ionizing radiation. To quantify the effects of exposure to environmental radionuclides on mitochondrial DNA (mtDNA) dynamics in wildlife, bank voles (Myodes glareolus) were collected from the chernobyl exclusion zone (CEZ), where animals are exposed to elevated levels of radionuclides, and from uncontaminated areas within the CEZ and elsewhere in Ukraine. Brains of bank voles from outside the CEZ were characterized by low mtDNA copy number and low mtDNA damage; by contrast, bank voles within the CEZ had high mtDNA copy number and high mtDNA damage, consistent with putative damaging effects of elevated radiation and a compensatory response to maintain sufficient functioning mitochondria. In animals outside the CEZ, the expression levels of PGC-1α gene and mtDNA copy number were positively correlated as expected from this gene’s prominent role in mitochondrial biogenesis; this PGC-1α-mtDNA copy number association is absent in samples from the CEZ. Our data imply that exposure to radionuclides is associated with altered mitochondrial dynamics, evident in level of mtDNA and mtDNA damage and the level of activity in mitochondrial synthesis.

• Publisher: Springer Nature B.V
• Subject: Animals / Copy number / Deoxyribonucleic acid / DNA / Environmental exposure / Exclusion zones / Exposure / Gene expression / Ionizing radiation / Mitochondria / Mitochondrial DNA / Oxidative stress / Radiation damage / Radioisotopes / Rodents / Wildlife