Transcriptome Analysis of the Carmine Spider Mite,Tetranychus cinnabarinus(Boisduval, 1867) (Acari: Tetranychidae), and Its Response toβ-Sitosterol

Abstract

Tetranychus cinnabarinus(Acari: Tetranychidae) is a worldwide polyphagous agricultural pest that has the title of resistance champion among arthropods. We reported previously the identification of the acaricidal compoundβ-sitosterol fromMentha piperitaandInula japonica. However, the acaricidal mechanism ofβ-sitosterol is unclear. Due to the limited genetic research carried out, wede novoassembled the transcriptome ofT. cinnabarinususing Illumina sequencing and conducted a differential expression analysis of control andβ-sitosterol-treated mites. In total, we obtained >5.4 G high-quality bases for each sample with unprecedented sequencing depth and assembled them into 22,941 unigenes. We identified 617 xenobiotic metabolism-related genes involved in detoxification, binding, and transporting of xenobiotics. A highly expanded xenobiotic metabolic system was found in mites.T. cinnabarinusdetoxification genes—including carboxyl/cholinesterase and ABC transporter class C—were upregulated afterβ-sitosterol treatment. Defense-related proteins, such as Toll-like receptor, legumain, and serine proteases, were also activated. Furthermore, other important genes—such as the chloride channel protein, cytochromeb, carboxypeptidase, peritrophic membrane chitin binding protein, and calphostin—may also play important roles in mites’ response toβ-sitosterol. Our results demonstrate that high-throughput-omics tool facilitates identification of xenobiotic metabolism-related genes and illustration of the acaricidal mechanisms ofβ-sitosterol.