DNA repair in plant mitochondria - a complete base excision repair pathway in potato tuber mitochondria

TY - JOUR

T1 - DNA repair in plant mitochondria - a complete base excision repair pathway in potato tuber mitochondria

AU - Ferrando, Beatriz

AU - Furlanetto, Ana L D M

AU - Gredilla, Ricardo

AU - Havelund, Jesper F

AU - Hebelstrup, Kim H

AU - Møller, Ian M

AU - Stevnsner, Tinna

N1 - © 2018 Scandinavian Plant Physiology Society.

PY - 2019/6

Y1 - 2019/6

N2 - Mitochondria are one of the major sites of reactive oxygen species (ROS) production in the plant cell. ROS can damage DNA, and this damage is in many organisms mainly repaired by the base excision repair (BER) pathway. We know very little about DNA repair in plants especially in the mitochondria. Combining proteomics, bioinformatics, western blot and enzyme assays, we here demonstrate that the complete BER pathway is found in mitochondria isolated from potato (Solanum tuberosum) tubers. The enzyme activities of three DNA glycosylases and an apurinic/apyrimidinic (AP) endonuclease (APE) were characterized with respect to Mg 2+ dependence and, in the case of the APE, temperature sensitivity. Evidence for the presence of the DNA polymerase and the DNA ligase, which complete the repair pathway by replacing the excised base and closing the gap, was also obtained. We tested the effect of oxidative stress on the mitochondrial BER pathway by incubating potato tubers under hypoxia. Protein carbonylation increased significantly in hypoxic tuber mitochondria indicative of increased oxidative stress. The activity of two BER enzymes increased significantly in response to this oxidative stress consistent with the role of the BER pathway in the repair of oxidative damage to mitochondrial DNA.

AB - Mitochondria are one of the major sites of reactive oxygen species (ROS) production in the plant cell. ROS can damage DNA, and this damage is in many organisms mainly repaired by the base excision repair (BER) pathway. We know very little about DNA repair in plants especially in the mitochondria. Combining proteomics, bioinformatics, western blot and enzyme assays, we here demonstrate that the complete BER pathway is found in mitochondria isolated from potato (Solanum tuberosum) tubers. The enzyme activities of three DNA glycosylases and an apurinic/apyrimidinic (AP) endonuclease (APE) were characterized with respect to Mg 2+ dependence and, in the case of the APE, temperature sensitivity. Evidence for the presence of the DNA polymerase and the DNA ligase, which complete the repair pathway by replacing the excised base and closing the gap, was also obtained. We tested the effect of oxidative stress on the mitochondrial BER pathway by incubating potato tubers under hypoxia. Protein carbonylation increased significantly in hypoxic tuber mitochondria indicative of increased oxidative stress. The activity of two BER enzymes increased significantly in response to this oxidative stress consistent with the role of the BER pathway in the repair of oxidative damage to mitochondrial DNA.

KW - DNA Glycosylases/genetics

KW - DNA Repair/genetics

KW - DNA, Mitochondrial/genetics

KW - DNA, Plant/genetics

KW - DNA-(Apurinic or Apyrimidinic Site) Lyase/genetics

KW - DNA-Directed DNA Polymerase/genetics

KW - Mitochondria/genetics

KW - Reactive Oxygen Species/metabolism

KW - Solanum tuberosum/genetics

UR - http://www.scopus.com/inward/record.url?scp=85052820499&partnerID=8YFLogxK

U2 - 10.1111/ppl.12801

DO - 10.1111/ppl.12801

M3 - Journal article

C2 - 30035320

SN - 0031-9317

VL - 166

SP - 494

EP - 512

JO - Physiologia Plantarum

JF - Physiologia Plantarum

IS - 2

ER -