Analysis of DNA Repair and Protection in the Tardigrade Ramazzottius varieornatus and Hypsibius dujardini after Exposure to UVC Radiation
Horikawa, Daiki D. and Cumbers, John and Sakakibara, Iori and Rogoff, Dana and Leuko, Stefan and Harnoto, Raechel and Arakawa, Kazuharu and Katayama, Toshiaki and Kunieda, Takekazu and Toyoda, Atsushi and Fujiyama, Asao and Rothschild, Lynn J. (2013) Analysis of DNA Repair and Protection in the Tardigrade Ramazzottius varieornatus and Hypsibius dujardini after Exposure to UVC Radiation. PLoS One, 8 (6: e64793). PLOS. DOI: 10.1371/journal.pone.0064793. ISSN 1932-6203.
Full text not available from this repository.
Tardigrades inhabiting terrestrial environments exhibit extraordinary resistance to ionizing radiation and UV radiation although little is known about the mechanisms underlying the resistance. We found that the terrestrial tardigrade Ramazzottius varieornatus is able to tolerate massive doses of UVC irradiation by both being protected from forming UVCinduced thymine dimers in DNA in a desiccated, anhydrobiotic state as well as repairing the dimers that do form in the hydrated animals. In R. varieornatus accumulation of thymine dimers in DNA induced by irradiation with 2.5 kJ/m² of UVC radiation disappeared 18 h after the exposure when the animals were exposed to fluorescent light but not in the dark. Much higher UV radiation tolerance was observed in desiccated anhydrobiotic R. varieornatus compared to hydrated specimens of this species. On the other hand, the freshwater tardigrade species Hypsibius dujardini that was used as control, showed much weaker tolerance to UVC radiation than R. varieornatus, and it did not contain a putative phrA gene sequence. The anhydrobiotes of R. varieornatus accumulated much less UVC-induced thymine dimers in DNA than hydrated one. It suggests that anhydrobiosis efficiently avoids DNA damage accumulation in R. varieornatus and confers better UV radiation tolerance on this species. Thus we propose that UV radiation tolerance in tardigrades is due to the both high capacities of DNA damage repair and DNA protection, a two-pronged survival strategy.
|Title:||Analysis of DNA Repair and Protection in the Tardigrade Ramazzottius varieornatus and Hypsibius dujardini after Exposure to UVC Radiation|
|Journal or Publication Title:||PLoS One|
|In Open Access:||Yes|
|In ISI Web of Science:||Yes|
|Keywords:||UVC radiation, Tardigrades, extraordinary resistance, DNA repair|
|HGF - Research field:||Aeronautics, Space and Transport|
|HGF - Program:||Raumfahrt|
|HGF - Program Themes:||R FR - Forschung unter Weltraumbedingungen|
|DLR - Research area:||Raumfahrt|
|DLR - Program:||R FR - Forschung unter Weltraumbedingungen|
|DLR - Research theme (Project):||R - Vorhaben Strahlenbiologie|
|Institutes and Institutions:||Institute of Aerospace Medicine > Radiation Biology|
|Deposited By:||Kerstin Kopp|
|Deposited On:||20 Jun 2013 08:15|
|Last Modified:||20 Jun 2013 08:15|
Repository Staff Only: item control page