Salt stress triggers generation of oxygen free radicals and DNA breaks in Physcomitrella patens protonema

0532865 - ÚEB 2021 RIV NL eng J - Journal Article
Zvanarou, S. - Vágnerová, Radka - Mackievic, V. - Usnich, S. - Smolich, I. - Sokolik, A. - Yu, M. - Huang, X. - Angelis, Karel - Demidchik, V.
Salt stress triggers generation of oxygen free radicals and DNA breaks in Physcomitrella patens protonema.
Environmental and Experimental Botany. Roč. 180, December (2020), č. článku 104236. ISSN 0098-8472. E-ISSN 1873-7307
R&D Projects: GA MŠMT LTC17047
Institutional support: RVO:61389030
Keywords : Abiotic stress * Antioxidants * Comet assay * Double-strand DNA breaks * Hydroxyl radicals * Physcomitrella patens * Protonema * Reactive oxygen species * Salinity * Single-strand DNA breaks
OECD category: Biochemistry and molecular biology
Impact factor: 5.545, year: 2020
Method of publishing: Open access
http://doi.org/10.1016/j.envexpbot.2020.104236

One of the early reactions of plants to high levels of NaCl is the generation of reactive oxygen species (ROS), which is critical for stress signaling, Na+ extrusion, oxidative damage and programmed cell death (PCD) under salt stress. Using moss Physcomitrella patens protonema as a model system, we have tested whether ROS generation and DNA degradation can be induced by salinity in Bryophyta. We have shown with dihydroethidium in vivo test that toxic NaCl concentrations significantly stimulate ROS production. The pharmacological analysis carried out using superoxide dismutase, catalase, dimethyl sulfoxide, thiourea and spermine outlines the superoxide and hydroxyl radicals as major NaCl-induced species. Using Comet assay, we have found that NaCl affects the DNA stability in ROS-dependent manner, increasing both single and double strand DNA breaks (SSBs and DSBs, respectively). Surprisingly, DSBs were induced by NaCl to a lesser extent than SSBs. This is indicative of an unexpected and sophisticated action of NaCl on moss genome including DSBs through PCD and SSBs caused by hydroxyl radical-induced DNA oxidation or transposon rearrangement. We also report a relatively high sensitivity of Physcomitrella patens protonema to NaCl compared to later developmental stages of this moss, suggesting that dividing cells are more sensitive to NaCl than other tissues.
Permanent Link: http://hdl.handle.net/11104/0311246