Identification of the transcriptome profile of Miamiensis avidus after mebendazole treatment

Abstract

Background: The scuticociliate <i>Miamiensis avidus</i> is a major pathogenic agent that causes significant economic losses in the flounder aquaculture industry. Many different types of drugs are being tested to control this disease, including mebendazole, which is a broad-spectrum antiprotozoal agent. The purpose of this study was to determine whether mebendazole worked <i>in vitro</i> against <i>M. avidus</i> and to explore its mechanism of action. Methods: Transcriptome and gene ontology analyses were conducted to investigate the specifically expressed gene profile. We confirmed the cytotoxic effect of mebendazole against <i>M. avidus</i> when it was applied intermittently for a total of three times. We also identified differentially expressed genes using transcriptome analysis. Results: Most of the upregulated genes were membrane transport-related genes, including Na⁺/K⁺-ATPase. Most of the downregulated genes were categorized into three groups: tubulin-related, metabolism-related, and transport-related genes. The expression levels of glucose uptake-related genes decreased due to the inhibition of tubulin polymerization, but this was not statistically significant.Conclusions: Our results demonstrate that intermittent treatment with mebendazole has a significant cytotoxic effect on <i>M. avidus</i>. Furthermore, mebendazole induces downregulation of the tubulin-alpha chain and metabolism-related genes. It is presumed that this leads to a glucose shortage and the death of <i>M. avidus</i>. Transcriptome analysis will provide useful clues for further studies on mebendazole applications for scutica control.