Academic Journals Database
Disseminating quality controlled scientific knowledge

Dynamics of Protein Phosphatase Gene Expression in Corbicula fluminea Exposed to Microcystin-LR and to Toxic Microcystis aeruginosa Cells

Author(s): José Carlos Martins | João Machado | António Martins | Joana Azevedo | Luís OlivaTeles | Vitor Vasconcelos

Journal: International Journal of Molecular Sciences
ISSN 1422-0067

Volume: 12;
Issue: 12;
Start page: 9172;
Date: 2011;
Original page

Keywords: C. fluminea | cyanotoxins | gene expression | microcystin-LR | protein phosphatases

This study investigated the in vivo effects of microcystins on gene expression of several phosphoprotein phosphatases (PPP) in the freshwater clam Corbicula fluminea with two different exposure scenarios. Clams were exposed for 96 h to 5 µg L−1 of dissolved microcystin-LR and the relative changes of gene expression of three different types of PPP (PPP1, 2 and 4) were analyzed by quantitative real-time PCR. The results showed a significant induction of PPP2 gene expression in the visceral mass. In contrast, the cyanotoxin did not cause any significant changes on PPP1 and PPP4 gene expression. Based on these results, we studied alterations in transcriptional patterns in parallel with enzymatic activity of C. fluminea for PPP2, induced by a Microcystis aeruginosa toxic strain (1 × 105 cells cm−3) during 96 h. The relative changes of gene expression and enzyme activity in visceral mass were analyzed by quantitative real-time PCR and colorimetric assays respectively. The clams exhibited a significant reduction of PPP2 activity with a concomitant enhancement of gene expression. Considering all the results we can conclude that the exposure to an ecologically relevant concentration of pure or intracellular microcystins (-LR) promoted an in vivo effect on PPP2 gene expression in C. fluminea.
Save time & money - Smart Internet Solutions      Why do you need a reservation system?