De Novo Characterization of Japanese Scallop Mizuhopecten yessoensis Transcriptome and Analysis of Its Gene Expression following Cadmium Exposure

Abstract

BackgroundJapanese scallop has been cultured on a large-scale in China for many years. However, serious marine pollution in recent years has resulted in considerable loss to this industry. Moreover, due to the lack of genomic resources, limited research has been carried out on this species. To facilitate the understanding at molecular level immune and stress response mechanism, an extensive transcriptomic profiling and digital gene expression (DGE) database of Japanese scallop upon cadmium exposure was carried out using the Illumina sequencing platform.ResultsRNA-seq produced about 112 million sequencing reads from the tissues of adult Japanese scallops. These reads were assembled into 194,839 non-redundant sequences with open reading frame (ORF), of which 14,240 putative amino acid sequences were assigned biological function annotation and were annotated with gene ontology and eukaryotic orthologous group terms. In addition, we identified 720 genes involved in response to stimulus and 302 genes involved in immune-response pathways. Furthermore, we investigated the transcriptomic changes in the gill and digestive gland of Japanese scallops following cadmium exposure using a tag-based DGE system. A total of 7,556 and 3,002 differentially expressed genes were detected, respectively, and functionally annotated with KEGG pathway annotations.ConclusionThis study provides a comprehensive transcripts sequence resource for the Japanese scallop and presents a survey of gene expression in response to heavy metal exposure in a non-model marine invertebrate via the Illumina sequencing platform. These results may contribute to the in-depth elucidation of the molecular mechanisms involved in bivalve responses to marine pollutants.

Transcriptome Profiling Analysis of Wolf Spider Pardosa pseudoannulata (Araneae: Lycosidae) after Cadmium Exposure

“…Numerous studies focused on metal transporters in both plants and animals have been reported [19,23,39,40]. ATP-binding cassette (ABC) family transporters are important heavy metal transporters and interact with a wide range of chemicals including metals by pumping them across the cell membrane to maintain of cellular metal homeostasis [41,42].…”

“…Comparing the enriched DEGs of P. pseudoannulata in association with varying concentrations of Cd exposure, the “cell surface receptor signalling pathway” (part of BP, GO: 0007166) and “signal transducer activity” (part of MF, GO: 0004871) were significantly enriched. Various signalling pathways have been demonstrated to be associated with Cd exposure [19,45]. MAPK pathway is usually known to be activated by Cd via ROS generation, which is associated with signal transduction in response to oxidative stress, thus, also plays an essential role in eliminating oxidative damaged cells [46,47].…”

“…Heat shock proteins (Hsps) are critical factors during the process of environmental stress [19,48]. Genes encoding for Hsps, which play a vital role in the transport, folding, and assembly of proteins, are induced by various causal agents such as heavy metals [49,50,51].…”

“…Though the genes related to Cd response have been widely studied in many vertebrate and invertebrate [19,20,21], only a few genes of spider responding to heavy metals have been reported previously. The wolf spider Pardosa pseudoannulata ( P. pseudoannulata ) is one of the most common species of wandering spiders in agricultural fields in China, and acts as one of the most important natural enemies to reduce pest populations, such as rice plant hoppers and leafhoppers [22].…”

The Role of Transcriptomics: Physiological Equivalence Based on Gene Expression Profiles

“…Various different models including fungus , plants (Oono et al, 2014;He et al, 2015;Xu et al, 2015;Oono et al, 2016), mollusk (Meng et al, 2013), fish (Bougas et al, 2013), mouse (Hu et al, 2014), and human cells (Cartularo et al, 2016) are being used to assess cadmium stress. Huang et al (2012) reported that perfluorooctane sulfonate affects the expression of genes related to neurobehavioral defects, mitochondrial dysfunction, and the metabolism of proteins and fats.…”