Molecular cloning of manganese superoxide dismutase gene in the cladoceran Daphnia magna: effects of microcystin, nitrite, and cadmium on gene expression profiles.
Superoxide dismutases (SODs) are metalloenzymes that represent one important line of defense against oxidative stress produced by reactive oxygen species in aerobic organisms. Generally, waterborne pollutants caused by irregular anthropogenic activities often result in oxidative damage in aquatic organisms. The aim of this study was to molecularly characterize the manganese superoxide dismutase gene (Dm-MnSOD) in the waterflea, Daphnia magna, and evaluate the mRNA expression patterns quantified by real-time PCR after exposure to three common waterborne pollutants (microcystin-LR, nitrite, and cadmium). The results showed that the full-length Dm-MnSOD sequence consists of 954 bp nucleotides, encoding 215 amino acids, showing well-conserved domains that are required for metal binding and several common characteristics, such as two MnSOD domains. The deduced amino acid sequence of Dm-MnSOD shared over 70% similarity with homologues from Bythograea thermydron, Dromia personata, Cancer pagurus, and Scylla paramamosain. Dm-MnSOD gene expression was up-regulated in response to exposure to the three chemicals tested. The overall results indicated that Dm-MnSOD gene is an inducible gene and potential biomarker indicating these pollutants in the environment.
Jiangsu Key Laboratory for Biodiversity and Biotechnology, School of Biological Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, China.
Kai
K
Lyu
Jiangsu Key Laboratory for Biodiversity and Biotechnology, School of Biological Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, China.
Xuexia
X
Zhu
Jiangsu Key Laboratory for Biodiversity and Biotechnology, School of Biological Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, China.
Rui
R
Chen
State Key Laboratory for Lake Science and Environment, Nanjing Institute of Geography and Limnology, the Chinese Academy of Sciences, Nanjing 210008, China.
Yafen
Y
Chen
Jiangsu Key Laboratory for Biodiversity and Biotechnology, School of Biological Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, China. Electronic address: yangzhou@njnu.edu.cn.
Zhou
Z
Yang
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015415:Biomarkers / Q000032:analysis; D002104:Cadmium / Q000633:toxicity*; D003621:Daphnia / Q000145:classification / Q000187:drug effects*; D005786:Gene Expression Regulation / Q000187:drug effects*; D052998:Microcystins / Q000633:toxicity*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009573:Nitrites / Q000633:toxicity*; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D013482:Superoxide Dismutase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000633:toxicity
D015415:Biomarkers; D052998:Microcystins; D009573:Nitrites; D014874:Water Pollutants, Chemical; D002104:Cadmium; C078588:microcystin; D013482:Superoxide Dismutase
Antioxidation; Biomarker; Cladoceran; Enzyme activity; Oxidative stress