Sequencing of Transcriptome and Small RNA Revealed the Xenobiotic Metabolism-Related Genes and Potential Regulatory miRNA in Asian Tramp Snail.

Qun Yang,Jinjun Wang,Jinzhi Niu,Biyue Ding,Wanjun Yang,Feng Shang

doi:10.3389/fgene.2020.595166

Abstract

The Asian tramp snail, Bradybaena similaris (Ferusssac), is an invasive land snail species and has been a rising agricultural pest in south of China. As a pest, it also plays a role in transmission of Angiostrongylus cantonensis. However, present studies on this species are rare and the molecular information is limited. For this purpose, we sequenced the transcriptome and small RNA of B. similaris collected from citrus orchards. In total, 89,747 unigenes with an N50 size of 1287 bp and an average length of 817 bp were generated from ∼8.9 Gb transcriptome and 31 Mb clean reads were generated from ∼36 Mb small RNA library. To demonstrate the usefulness of these two datasets, we analyzed a series of genes associated with xenobiotic metabolism and core RNAi machinery. Analysis of the transcripts resulted in annotation of 126 putative genes encoding cytochrome P450 monooxygenases (CYP, 45), carboxyl/cholinesterases (CCE, 13), glutathione-S-transferases (GST, 24), and ATP-binding cassette transporters (ABC, 44). Analysis of the small RNA detected 42 miRNAs. In addition, four genes involved in small RNA pathways (miRNA, piRNA, and siRNA) were identified, and a total of 430 genes that can be targeted by miRNAs were predicted. Moreover, we found that a few miRNAs could target certain genes involved in xenobiotic metabolism. Therefore, we believe that these two datasets and the characterization of the identified/predicted genes will facilitate the molecular study of this species as well as other land snails with agricultural importance.

Highlights

The Asian tramp snail, Bradybaena similaris (Mollusca: Gastropoda: Pulmonata: Stylommatophora: Bradybaenidae), is an invasive land snail that has been a widely distributed pest
Based on the phylogenetic analysis, which is helpful for investigating the evolutionary relationships between genes among species, we identified a total of 126 genes related to potential xenobiotic metabolism, including 45 P450s, 13 CCEs, 24 GSTs, and 44 ATP-binding cassette transporters (ABCs)
We identified 42 miRNAs based on the constructed small RNA library, which is less than the number of miRNA in P. vulgata (45), L. gigantea (59), and B. glabrata (209) (Kenny et al, 2015; Adema et al, 2017)

Summary

Introduction

The Asian tramp snail, Bradybaena similaris (Mollusca: Gastropoda: Pulmonata: Stylommatophora: Bradybaenidae), is an invasive land snail that has been a widely distributed pest. Transcriptome and miRNA of B. similaris harmful to some economically important plants such as coffee and fruits, which has directly resulted in great economic losses (Serniotti et al, 2019) They start to come out looking for food at the beginning of March (temperature >10◦C) and are most active from April to June (10–30◦C) (Wang et al, 2016). This pest has been reported as intermediate hosts of trematodes and nematodes (Alves et al, 2014; Morassutti et al, 2014), and it has been one of known intermediate hosts of Angiostrongylus cantonensis in China (Shan et al, 2008). It should be highlighted that the compounds present in the composition of plant-derived molluscicides are complex and some of them have high toxicity to nontarget organisms, so evaluation and demonstration of the ecotoxicity information will be needed before using in the field (Pereira et al, 2020)

Methods

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Discussion

Conclusion