The metallothionein gene from the Oriental river prawn Macrobrachium nipponense (De Haan, 1849): characterization and expression in response to hypoxia and reoxygenation

Abstract

Since mammals make use of metallothioneins (MTs) to protect against hypoxia-generated reactive oxygen species (ROS), here we investigate whether MTs have the same effect in the Oriental river prawnMacrobrachium nipponense(De Haan, 1849). Levels ofM. nipponenseMT (MnMT) mRNA in different tissues were analysed using a real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). We found that MnMT is differentially expressed in the haemocytes, intestine, gills, heart, hepatopancreas and muscle. The highest levels of expression occurred in the hepatopancreas and heart. The results of the qRT-PCR and Western blot indicated that MnMT mRNA and protein expression in the hepatopancreas increased significantly in response to hypoxia 24 h and followed by 1 h reoxygenation compared to normoxia. Similarly, there were also significant increases in respiratory bursts and ROS production in the hepatopancreas. The MT protein possibly has a protective effect against ROS generated during hypoxia and reoxygenation stimuli.