PEREZ Alejandra patricia
congresos y reuniones científicas
Photobiology strategies in freshwater zooplankton, Boeckella genus as a study case
Congreso; 16th International Congress on Photobiology; 2014
Institución organizadora:
Universidad Nacional de Córdoba - International Union of Photobiology
In this overview, the UVR effects on freshwater copepods are examined focusing on the south-American widespread genus Boeckella. Interspecific variations of UV absorbing compounds were reported from natural Boeckella populations, showing that the qualitative and quantitative composition depend, largely on the light history of the species [1]. Kinetic rates of mycosporine like aminoacids (MAAs) calculated in several Boeckella species showed that MAAs concentration was related not only with UV exposure but also with the temperature [2]. From these experiments, also emerge the hypothesis that MAAs in Boeckella comes from an alternative source. Later, Pérez and coworkers suggested that these compounds would be produced by copepod associated prokaryotes [3-4]. The survivorship patterns of Boeckella suggest an acute sensitivity to increasing temperature reflecting their adaptation to high solar radiation exposure as well as to temperate and cold environments [5]. Intraspecific variation in photoprotection strategies were widely explored in Boeckella gracilipes. Large variability in the content of MAAs was found among populations inhabiting humic colourfull environments as compared to clear optically environments [1]. Moreover, some populations have a negligible photoenzimatic repair (PER) capacity and showed a behavioural avoidance of photodamage [6]. On the other hand, the activity of antioxidant enzymes measured in populations from lakes in a natural gradient of dissolved organic carbon (DOC) suggest that both low and high DOC concentration would enhance enzymatic activity because of direct UVR or through indirect effect of DOC-UVR interaction [7]. Altogether, these results highlight that sensitivity to UV can vary depending on extrinsic and intrinsic factors and the access to several different protective systems may considerably improve protection from UVR and thereby increase the animal?s fitness.   [1] B. Tartarotti, G. Baffico, P. Temporetti and H. Zagarese, J. Plankton Res, 2004, 26, 753. [2] P. García, M. Dieguez, M. Ferraro, H. Zagarese and P. Pérez, Photochem. Photobiol, 2010, 86, 353 [3] P. Perez, D. Libkind,M. Dieguez, M. Summerer, B. Sonntag, R. Sommaruga. et al. Photochem. Photobiol, 2006, 5, 25. [4] P. Pérez, M. Ferraro and H. Zagarese, Freshwater Biol, 2012, 57, 993 [5] P. García and M. Diéguez, Crustaceana, 2014, 87, 291. [6] H. Zagarese, M. Feldman and C. Williamson, J. Plankton Res, 19,357 [7] M. Souza, B. Modenutti and E. Balseiro, Water Air Soil Poll, 2007, 183, 49