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ABSTRACT Ionic liquids (ILs) are widely used as reaction media in various commercial applications. Many reports have indicated that most ILs are poorly decomposed by microorganisms and are toxic to aquatic organisms. In this study, differential gene expression profiling was conducted using a suppression subtraction hybridization cDNA library from hepatic tissue of the loach ( Paramisgurnus dabryanus) after exposure to 1-hexadecyl-3-methylimidazolium chloride ([C16mim]Cl), a representative IL. Two hundred and fifty-nine differentially expressed candidate genes, whose expression was altered by >2.0-fold by the [C16mim]Cl treatment, were identified, including 127 upregulated genes and 132 downregulated genes. A gene ontology analysis of the known genes isolated in this study showed that [C16mim]Cl-responsive genes were involved in cell cycle, stimulus response, defense response, DNA damage response, oxidative stress responses, and other biological responses. To identify candidate genes that may be involved in [C16mim]Cl-induced toxicity, 259 clones were examined by Southern blot macroarray hybridization, and 20 genes were further characterized using quantitative real-time polymerase chain reaction. Finally, six candidate genes were selected, including three DNA damage response genes, two toxic substance metabolic genes, and one stress protein gene. Our results indicate that these changes in gene expression are associated with [C16mim]Cl-induced toxicity, and that these six candidate genes can be promising biomarkers for detecting [C16mim]Cl-induced toxicity. Therefore, this study demonstrates the use of a powerful assay to identify genes potentially involved in [C16mim]Cl toxicity, and it provides a foundation for the further study of related genes and the molecular mechanism of [C16mim]Cl toxicity. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 404-416, 2017. [ABSTRACT FROM AUTHOR]

This study was a preliminary step to evaluate the acute toxicity of 1-methyl-3-octylimidazolium chloride ([C8mim]Cl) on loach (Misgurnus anguillicaudatus) by determining the effects on hepatic antioxidant enzyme activities and by the comet assay. The results showed that [C8mim]Cl had acute toxicity at concentrations above 20 mg L−1, inducing oxidative stress and genotoxicity on fish liver cells. In respect to enzyme activities, [C8mim]Cl induced changes in the activities of superoxide dismutase, catalase, and glutathione content the livers of fish exposed at 20–80 mg L−1. [C8mim]Cl at the same exposure level caused a remarkable increase in malondialdehyde level. The comet assay indicated that [C8mim]Cl at 20–80 mg L−1induced genotoxicity in liver cells. With increased exposure concentration and time, the two comet parameters trailing rate and tail moment were significantly increased, with significant differences (P< 0.05) observed between control group and each treatment group. The present study shows that ionic liquids can be a threat to the health of aquatic organism when accidentally released to aquatic ecosystems. [ABSTRACT FROM PUBLISHER]

A number of genetic studies have established that Sox10 is a transcription factor associated with neurogenesis in vertebrates. We have isolated a homologue of Sox10 gene from the brain of Misgurnus anguillicaudatus by using homologous cloning and RACE method, designated as MaSox10b. The full-length cDNA of MaSox10b contained a 311 bp 5′UTR, a 312 bp 3′UTR and an ORF encoding a putative protein of 490 amino acids with a characteristic HMG-box DNA-binding domain of 79 amino acids (aa: 105-183). Phylogenetic tree shows that the MaSOX10b fits within the Sox10 clade and clusters firmly into Sox10b branches. During embryogenesis, MaSox10b was first detected in gastrulae stage. From somitogenesis stage and thereafter, distinct expression was observed in the medial neural tube, extending from the hindbrain through the posterior trunk. Taken together, these preliminary findings suggested that MaSox10b is highly conserved during vertebrate evolution and involved in a wide range of developmental processes including embryogenesis and neurogenesis. [ABSTRACT FROM AUTHOR]

Teleost fins can regenerate accurate position-matched structure and function after amputation. However, we still lack systematic transcriptional profiling and methodologies to understand the molecular basis of fin regeneration. After histological analysis, we established a suppression subtraction hybridization library containing 418 distinct sequences expressed differentially during the process of blastema formation and differentiation in caudal fin regeneration. Genome ontology and comparative analysis of differential distribution of our data and the reference zebrafish genome showed notable subcategories, including multi-organism processes, response to stimuli, extracellular matrix, antioxidant activity, and cell junction function. KEGG pathway analysis allowed the effective identification of relevant genes in those pathways involved in tissue morphogenesis and regeneration, including tight junction, cell adhesion molecules, mTOR and Jak-STAT signaling pathway. From relevant function subcategories and signaling pathways, 78 clones were examined for further Southern-blot hybridization. Then, 17 genes were chosen and characterized using semi-quantitative PCR. Then 4 candidate genes were identified, including F11r , Mmp9 , Agr2 and one without a match to any database. After real-time quantitative PCR, the results showed obvious expression changes in different periods of caudal fin regeneration. We can assume that the 4 candidates, likely valuable genes associated with fin regeneration, deserve additional attention. Thus, our study demonstrated how to investigate the transcript profiles with an emphasis on bioinformatics intervention and how to identify potential genes related to fin regeneration processes. The results also provide a foundation or knowledge for further research into genes and molecular mechanisms of fin regeneration. [ABSTRACT FROM AUTHOR]

Hsp70 is the most strongly induced in response to various cellular stresses and a good candidate for investigating its role in tissue injury. We firstly cloned full-length cDNA of hsp70 from Paramisgurnus dabryanus ( PdHsp70 ) by RACE method (GenBank: KP402408.1 ). Then regeneration and inflammation of fin were established by amputation and scratch respectively. Quantitative RT-PCR detected the PdHsp70 began to increase rapidly its expression at 1 days post amputation (dpa) and reached the peak at 2 dpa during fin regeneration. Its expression was also up-regulated at 2 days post scratch (dps) of inflammation but still significant weaker in comparison with it in regenerated fin at 2 dpa. Next, immunohistochemistry analysis of PdHsp70 showed that PdHsp70 located mainly in the deeper epidermis of regenerated fin and was stronger than its expression in the scratched inflammatory fin which was involved in whole epidermal. SDS-PAGE and Western blotting confirmed that the PdHsp70 protein expressed efficiently in Escherichia coli BL21. These findings have implied that PdHsp70 are implicated in different regulation of regeneration and inflammation in response to injury stimulation. During the regeneration, it is involved in the formation of wound epidermis by mediating cellular protection whereas it can modulate inflammatory by activating the innate immune response. [ABSTRACT FROM AUTHOR]

The present investigation was aimed to assess the effects of imidacloprid on the survival, genetic materials, hepatic transaminase activity and histopathology of loach ( Misgurnus anguillicaudatus ). The values of LC 50 (24, 48, 72 and 96 h) of imidacloprid were 167.7, 158.6, 147.9 and 145.8 mg/L, respectively, and the safety concentration was 42.55 mg/L. The erythrocyte micronuclei assays and the comet assay results showed that imidacloprid had genetic toxic effect on the loach erythrocytes. To assess the physiological and biochemical damage caused by imidacloprid, the activities of hepatic glutamic-pyruvic transaminase (GPT) and glutamic-oxalacetic transaminase (GOT) were measured and their values declined in treatment groups. Histological examination of testis revealed that imidacloprid treatment resulted in disorganized lobules and cysts structures. In the present work, we also investigated the joint toxicity of pesticides commonly used in paddy fields (imidacloprid and lambda-cyhalothrin) on M. anguillicaudatus , and confirmed that a synergistic effect existing in the binary mixtures. The results of our study provide relevant and comparable toxicity information that are useful for safety application of pesticides. [ABSTRACT FROM AUTHOR]