Enzymatic mechanisms of cyanobacterial toxin tolerance transfer to offspring in the Cladoceran Daphnia magna
Rafael Ortiz Rodríguez
129 pages, year of publication: 2012
price: 36.50 €
The effects of cyanobacterial toxins on zooplankton are very important for understanding the freshwater ecosystem. In this work we analyzed the effects of one of the most important toxins (microcystin-LR) on the freshwater zooplankter Daphnia magna. The age dependent effects were determined, showing that neonates and adults show different responses to acute exposure to microcystin-LR. In addition, transgenerational effects were analyzed by exposing acutely and chronically the progeny of exposed and non-exposed mothers. We found that given enough time and concentration of exposure of the mothers, the progeny are born with an increased response of the biotransformation enzyme (glutathione S transferase). Moreover, we show that these groups of Daphnids have reduced mortality when exposed to the toxin compared with the progeny from non-exposed mothers. These results explain the biochemistry behind the transgenerationally acquired tolerance to microcystin and helps understanding the energy transfer on freshwater food webs under toxic stress.