Ultraviolet damage and counteracting mechanisms in the freshwater copepod Boeckella poppei from the Antarctic Peninsula

• Main Authors: Vanina E. Rocco, Ruben Sommaruga, Marcela Ferraro, Horacio E. Zagarese
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2002
• Subjects: Antarctic; Antarctic Peninsula; Boeckella; Lake Boeckella; The Antarctic; Antarc*; Copepods
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.536.1393; http://www.aslo.org/lo/toc/vol_47/issue_3/0829.pdf

The process of ozone depletion over the Antarctic continent has resulted in the increase of incident ultraviolet-B (UVB) radiation, whose effects may be damaging to living organisms. To counteract the negative effects of ultraviolet radiation (UVR), aquatic organisms may display one or more strategies: (1) avoidance (i.e. deep distri-bution); (2) photoprotection through the use of ‘‘sunscreen’ ’ compounds, such as mycosporine-like amino acids (MAAs); and (3) enzymatic repair of the damage. The effects of UVR were assessed on four populations of the copepod Boeckella poppei from Antarctic lakes using laboratory and field experiments. The results were related to measurements of DNA enzymatic repair activity and MAA concentration. This is the first study that combines these measurements in zooplankton. Boeckella poppei was highly tolerant to UVR (LD50 5 2.2–2.78 J cm22). However, measurements of photorecovery (comparison of UVB mortality in the presence and absence of photoreactivating light) and dosage of photolyase activity indicated low rates of enzymatic repair, which may be the result of low temperatures typical of Antarctic lakes. Three different MAAs were identified, both in phytoplankton and copepods: porphyra-334, mycosporine-glycine, and shinorine. The population of B. poppei from Lake Boeckella had the lowest