INIBIOMA   20415
INSTITUTO DE INVESTIGACIONES EN BIODIVERSIDAD Y MEDIOAMBIENTE
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Oxidative stress in the copepod Boeckella gracilipes in Andean lakes: intra-specific differences
Reunión:
Congreso; Global Change and the Worlds Mountains; 2010
Resumen:
Calanoid copepods are dominant zooplankters in many nutrient poor
mountain lakes. In these ecosystems, high C:P ratios are associated with
high light-phosphorus ratios, thus, organisms living in these
transparent lakes would be constrained by potentially hazardous
ultraviolet radiation (UVR). In Andean North Patagonian lakes, the
success of the widespread calanoid copepod Boeckella gracilipes would
relay in intraespecific differences in photoprotective pigments
(carotenoids and mycosporine-like amino acids), elemental ratios (C:N:P)
and in antioxidant enzyme activities. We carried out experiments to
test how C:P ratios and photoprotective pigments combine to enhance
protection to UVR. We hypothesize that while carotenoids and MAAs
creates a direct protection, C:P ratio would affect the antioxidant
capacity and hence protection against damage in acetylcholinesterase
(AChE). Although carotenoid concentration was higher in organisms
inhabiting fishless high altitude lakes, the antioxidant enzyme
glutathione-S-transferase (GST) activity was also higher in these
copepods than in low altitude with higher sestonic C:P ratios. Changes
in solar radiation as well as in elemental ratios will affect cellular
mechanisms that will have important consequences in organisms such as
movement capacity.