Tissue specific metallothionein gene expression in air-breathing teleost, Channa punctata (Bloch)

Abstract

Cellular levels of specific transcripts or proteins are often measured in relation to a variety of biological events, using a selection of qualitative and quantitative methodologies. Changes in expression levels, measured in a native sentinel species may serve as biomarkers for the effects of environmental perturbations. A quantitative real-time reverse-transcriptase polymerase chain reaction study was conducted using freshwater air-breathing fish, Channa punctata (Bloch) as a test model for observing metallothionein mRNA expression pattern under the influence of varied concentrations of heavy metal, cadmium for an exposure span of 14 days. The findings revealed that metallothionein gene expression is a tissue specific phenomenon in C. punctata and liver is a prominent site for first-line defence during early exposure phase to cadmium, whereas kidney metallothionein mRNA indicates prolong presence of metal in the body.