[Show abstract][Hide abstract] ABSTRACT: The voltage-dependent anion channel (VDAC) is a highly conserved integral protein of mitochondria in different eukaryotic species. It forms a selective channel in the mitochondrial outer membrane that serves as the controlled pathway for small metabolites and ions. In this study, a VDAC gene, EcVDAC1, was isolated from orange-spotted grouper (Epinephelus coioides). The EcVDAC1 exhibits ubiquitous expression in various tissues of orange-spotted grouper and is upregulated in liver, gill, and spleen after stimulation with lipopolysaccharides (LPS). Subcellular localization analysis shows that the EcVDAC1 protein colocalized with the mitochondria. A caspase-3 assay demonstrates that overexpression of the EcVDAC1 induced apoptotic cell death in fathead minnow cells. The data presented in this study provide new information regarding the relationship between LPS and the EcVDAC1 gene, suggesting that the fish VDAC1 gene may play an important role in antibacterial immune response.
Journal of Biochemical and Molecular Toxicology 07/2014; 28(7). DOI:10.1002/jbt.21565 · 1.93 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This paper reports the complete mitochondrial genome (mitogenome) sequence of Channa maculate (Taiwan snakehead). The mitogenome of Taiwan snakehead was determined to be 16,558 bp in length. It contains 13 typical vertebrate protein-coding genes, 22 tRNA genes, 2 rRNA genes, 1 O(L) (putative light-strand origin of replication), and 1 putative control region (D-loop). This is the first report on the complete mitogenome sequence of Channa maculata.
Mitochondrial DNA 02/2013; 24(4). DOI:10.3109/19401736.2012.762578 · 1.21 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The Pearl River Delta (PRD) is located in the Southern part of China and is the main region for fish culture in Guangdong Province. In order to assess the potential health risks associated with dietary consumption of mercury, hair samples from 91 urban, town and fishing village residents, 37 species of fish, cereal, vegetables, and meat samples were collected. The average total mercury (THg) and methylmercury (MeHg) concentrations in hair were 1.08±0.94 and 0.58±0.59μg/g, respectively. Daily Hg intake via fish consumption is significantly correlated with THg and MeHg accumulated in human hair (r=0.48, p<0.01; r=0.43, p<0.01). The estimated daily intake of Hg via different food types showed that both fish and cereal consumption were the two main routes of Hg exposure for residents in the sampling areas. Besides food intake, smoking was also an important source for daily THg intake in the smoke group, contributing 11-18% to EDI of THg.
[Show abstract][Hide abstract] ABSTRACT: GRIM-19 is a nuclear encoded subunit of complex I that has been implicated in apoptosis. The protein participates in multiple functions including the innate immune response. GRIM-19 has been studied in humans and other mammals; however, fish GRIM-19 has not been well characterized. In this study, a new GRIM-19 gene, EcGRIM-19, was isolated from the orange-spotted grouper (Epinephelus coioides) cDNA library, which was constructed following LPS treatment. EcGRIM-19 is a 582-bp gene that encodes a 144-amino acid protein. The gene is a true ortholog of mammalian GRIM-19. EcGRIM-19 exhibits ubiquitous and constitutive expression in the different tissues of the orange-spotted grouper. The expression levels of EcGRIM-19 are altered in the gill, spleen, kidney and liver after induction with LPS. The subcellular localization analysis demonstrated that the EcGRIM-19 protein is localized predominantly in the mitochondria. In addition, amino acids 30-50 of the protein are responsible for the mitochondrial localization of EcGRIM-19. The caspase assay demonstrated that the overexpression of GRIM-19 enhanced the cellular sensitivity to interferon(IFN)-β- and retinoic acid (RA)-induced death in HeLa cells. The data presented in this study are important for further understanding the EcGRIM-19 gene function in fish.
[Show abstract][Hide abstract] ABSTRACT: V-set and immunoglobulin domain-containing protein 4 (VSIG4), a member of the immunoglobulin superfamily, plays an important role in the immune system. This study isolated and characterized a cDNA encoding VSIG4 (MaVSIG4) from the Asian yellow pond turtle (Mauremys mutica). The MaVSIG4 cDNA is 1840 bp long and contains an open reading frame of 1,182 bp that encodes a polypeptide of 372 amino acids. The genomic sequence of MaVSIG4 spans 7,682 bp, with six exons and five introns. The phylogenetic tree shows that MaVSIG4 is most closely related to Gallus gallus VSIG4. The expression analysis by real-time PCR reveals that MaVSIG4 is ubiquitously expressed in various healthy tissues, with a higher expression level in the liver. After immune stimulation, the expression level of MaVSIG4 sharply decreased in the liver, heart, and kidney at 12 h (P < 0.01). These results provide a basis for further study of the function of MaVSIG4 in the turtle's immune system.
[Show abstract][Hide abstract] ABSTRACT: Concentrations and distributions of selected fluoroquinolones (norfloxacin, ciprofloxacin and enrofloxacin) in water, sediments and nine kinds of fish species collected from 6 sites in two marine aquaculture regions of the Pearl River Delta, China, were analyzed by using high-performance liquid chromatography with fluorescence detector (HPLC). The results showed that the concentrations of ciprofloxacin and enrofloxacin were below the limits of quantification (LOQ) in all water samples except for norfloxacin. Norfloxacin and ciprofloxacin concentrations ranged from 1.88 to 11.20 ng g(-1) dry wt, 0.76-2.42 ng g(-1) dry wt in sediments collected from the Dapeng'ao region (sites 1-3) and ranged from 2.31 to 4.75 ng g(-1) dry wt, 1.26-1.76 ng g(-1) dry wt in sediments collected from the Hailing Island region (sites 4-6), respectively. However, no enrofloxacin was found in all sediment samples. The three fluoroquinolones (FQs) were detected in all fish samples, and the concentrations were higher in liver tissues than those in muscle tissues. The levels of norfloxacin were higher than ciprofloxacin and enrofloxacin in both liver and muscle tissues. Among the nine marine fish species, Siganus fuscescens from Hailing Island had a significantly high level of norfloxacin in liver tissue (254.58 ng g(-1) wet wt), followed by Sparus macrocephalus (133.15 ng g(-1) wet wt) from Dapeng'ao, and the lowest value was Lutianus argentimaculatus (5.18 ng g(-1) wet wt) from Hailing Island. The obtained results of FQs in present study do not represent a risk to the human health in Guangdong coastal area, based on the maximum residue limits (MRLs) established by Chinese Government and the acceptable daily intake (ADI) recommended by the Food and Agriculture Organization and World Health Organization (FAO/WHO).
Environmental Geochemistry and Health 09/2011; 34(3):323-35. DOI:10.1007/s10653-011-9420-4 · 2.57 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: During June through October 2008, numerous cultured largemouth bass (Micropterus salmoides) died in the Foshan area of Guangdong Province, China. Affected fish had ulcerations on the skin and muscle. Epithelioma papillosum cyprini (EPC) cell cultures inoculated with filtrates of muscle homogenates from the diseased fish developed the cytopathic effect (CPE) 5 days after inoculation at the primary passage. Transmission electron microscopy of the ulcerative muscle tissue and the infected EPC cells revealed a cytoplasmic, icosahedral virion that averaged 145 nm in diameter. Intramuscular injection of the virus (≥ 107.82 TCID50 ml−1) resulted in clinical signs of the disease and caused 100% mortality of healthy largemouth bass. In addition, the mandarinfish (Siniperca chuatsi) was susceptible to the virus after intramuscular injection of the virus (0.2 ml of 109.82 TCID50 ml−1), and the mortality was 20%. However, no death or clinical signs were found in grass carp (Ctenopharyngodon idella), bighead carp (Aristichthys nobilis), Nile tilapia (Oreochromis niloticus), crucian carp (Carassius carassius), common carp (Cyprinus carpio), and fancy carp (C. carpio) after experimental infection. DNA fragments of the viral major capsid protein (MCP) and DNA methyltransferase (MTase) were amplified and sequenced. Subsequent multiple alignment and phylogenetic analysis revealed that the virus is identical to doctor fish virus (DFV) and closely related to largemouth bass virus (LMBV).