Development of a rapid assay to detect the jellyfish Cyanea nozakii using a loop-mediated isothermal amplification method

Abstract

Blooms of the harmful jellyfish Cyanea nozakii, which are a severe nuisance to fisheries and tourisms, frequently occur in the northern East China Sea, Yellow Sea, and Bohai Sea. To provide early warning of this species, a simple and effective molecular method for identifying C. nozakii was developed using the loop-mediated isothermal amplification method (LAMP). The LAMP assay is highly specific and uses a set of four primers that target six different regions on the mitochondrial cytochrome c oxidase subunit I (COI) gene of C. nozakii. The amplification conditions, including the dNTP and betaine concentrations, the inner primer to outer primer concentration ratio, reaction time and temperature, were optimized. The LAMP assay amplified DNA extracted from tissue samples of C. nozakii but did not amplify DNA from other common scyphozoans and hydrozoans collected in the same region. In addition, the LAMP assay was more sensitive than conventional PCR. Therefore, the established LAMP assay is a sensitive, specific, fast, and easily performed method for detection of C. nozakii at different stages in their life cycle.

• Cyanea nozakii
• cytochrome c oxidase subunit I
• jellyfish blooms
• LAMP
• mitochondrial DNA

Acknowledgements

The authors thank Youfang Sun, Qianwen Qu, and Guoxiu Zhang for their assistance in the field investigation and experiment.

Declaration of interest

The authors report that they have no conflicts of interest. This work was supported by grants from the National Natural Science Foundation of China (No. 41206086), the Strategic Priority Research Program of Chinese Academy of Sciences (Nos. XDA05130703 and XDA11020405), and the Research Encouragement Foundation of Excellent Midlife-Youth Scientists of Shandong Province (No. BS2011HZ023).