title: UV-induced DNA damage inCyclops abyssorum tatricuspopulations from clear and turbid alpine lakes.
abstract: Zooplankton from clear alpine lakes thrive under high levels of solar UV radiation (UVR), but in glacially turbid ones they are more protected from this damaging radiation. Here, we present results from experiments done withCyclops abyssorum tatricusto assess UV-induced DNA damage and repair processes using the comet assay. Copepods were collected from three alpine lakes of differing UV transparency ranging from clear to glacially turbid, and exposed to artificial UVR. In addition, photoprotection levels [mycosporine-like amino acids (MAAs) and lipophilic antioxidant capacity] were estimated in the test populations. Similar UV-induced DNA damage levels were observed among the copepods from all lakes, but background DNA damage (time zero and dark controls) was lowest in the copepods from the glacially turbid lake, resulting in a higher relative DNA damage accumulation. Most DNA strand breaks were repaired after recovery in the dark. Low MAA concentrations were found in the copepods from the glacially turbid lake, while the highest levels were observed in the population from the most UV transparent lake. However, the highest lipophilic antioxidant capacities were measured in the copepods from the lake with intermediate UV transparency. Photoprotection and the ability to repair DNA damage, and consequently reducing UV-induced damage, are part of the response mechanisms in zooplankton to changes in water transparency caused by glacier retreat.
authors.affiliation: Laboratory of Aquatic Photobiology and Plankton Ecology , Institute of Ecology, University of Innsbruck , Technikerstraße 25, 6020 Innsbruck , Austria.
authors.forename: Barbara
authors.initials: B
authors.lastname: Tartarotti
authors.affiliation: Laboratory of Freshwater and Stress Ecology, Department of Biology , Humboldt-Universität Zu Berlin , Arboretum, Späthstraße 80/81, 12437 Berlin , Germany.
authors.forename: Nadine
authors.initials: N
authors.lastname: Saul
authors.affiliation: Laboratory of Freshwater and Stress Ecology, Department of Biology , Humboldt-Universität Zu Berlin , Arboretum, Späthstraße 80/81, 12437 Berlin , Germany.
authors.forename: Shumon
authors.initials: S
authors.lastname: Chakrabarti
authors.affiliation: Laboratory of Aquatic Photobiology and Plankton Ecology , Institute of Ecology, University of Innsbruck , Technikerstraße 25, 6020 Innsbruck , Austria.
authors.forename: Florian
authors.initials: F
authors.lastname: Trattner
authors.affiliation: Laboratory of Freshwater and Stress Ecology, Department of Biology , Humboldt-Universität Zu Berlin , Arboretum, Späthstraße 80/81, 12437 Berlin , Germany.
authors.forename: Christian E W
authors.initials: CE
authors.lastname: Steinberg
authors.affiliation: Laboratory of Aquatic Photobiology and Plankton Ecology , Institute of Ecology, University of Innsbruck , Technikerstraße 25, 6020 Innsbruck , Austria.
authors.forename: Ruben
authors.initials: R
authors.lastname: Sommaruga
keywords: UV radiation; antioxidants; comet assay; copepods; mycosporine-like amino acids; photoprotection