Molecular characterization of two glutathione peroxidase genes in Mytilus galloprovincialis and their transcriptional responses to sub-chronic arsenate and cadmium exposure

Authors

  • Q Wang Key Laboratory of Coastal Zone Environment Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, PR China
  • X Ning Yantai Oceanic Environmental Monitoring Central Station of SOA, Yantai 264006, PR China
  • Q Zhang China Agriculture University (Yantai), Yantai 264670, PR China
  • F Liu China Agriculture University (Yantai), Yantai 264670, PR China
  • H Wu Key Laboratory of Coastal Zone Environment Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, PR China
  • Y Zhang Key Laboratory of Coastal Zone Environment Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, PR China
  • J Zhao Key Laboratory of Coastal Zone Environment Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, PR China

Keywords:

cytosolic GPx, phospholipid-hydroperoxide GPx, arsenic, cadmium, bivalve, antioxidant enzyme

Abstract

Glutathione peroxidases (GPxs) are key enzymes in the antioxidant defense system of living
organisms, and protect organisms against oxidative stresses. In this study, the full-length cDNA
sequences encoding cytosolic GPx (MgcGPx) and phospholipid-hydroperoxide GPx (MgGPx4) were identified from Mytilus galloprovincialis. The mussels were exposed to 0, 1, 10, and 100 μg/L cadmium and arsenate for 30 days. The mRNA transcripts of these two genes and total GPx activity were examined in the gills and digestive gland after contaminants exposure. The mussels exposed to cadmium and arsenate responded mainly by down-regulating MgcGPx and MgGPx4 mRNA transcription in gills and up-regulating transcription in digestive gland. However, total GPx activities increased following cadmium exposure but decreased after arsenate stress in both tissues. These results suggest that MgcGPx and MgGPx4 perhaps play an important role in maintaining cellular redox homeostasis and protecting M. galloprovincialis against cadmium and arsenate toxicity. It can also be inferred that these genes have the potential to be used as molecular biomarkers for assessing cellular stress and toxicity of contaminants in this mussel.

Downloads

Published

2014-05-16

Issue

Vol. 11 No. 1 (2014)

Section

Research Reports