Search

Glycyrrhiza uralensis Fisch., a well-known medicinal plant, contains flavonoids including liquiritigenin and isoliquiritigenin, and their corresponding glycoside liquiritin and isoliquiritin. Although some genes encoding UDP-glycosyltransferases (UGTs) have been functionally characterized in G. uralensis, other UGTs mechanisms of glycosylation remain to be elucidated. Against this background the aim of the present study included cloning and characterization of two full-length cDNA clones of GuUGT isoforms from the UGT multigene family. These included GuUGT2 (NCBI acc. MK341791) and GuUGT3 (NCBI acc. MK341793) with an ORF of 1473 and 1332 bp, respectively. Multiple alignments and phylogenetic analysis revealed GuUGTs protein of Glycine max had a high homology to that of other plants. Meanwhile, quantitative real-time PCR was performed to detect the transcript levels of GuUGTs in different tissues. The results indicated that GuUGTs was more expressed in roots as compared to the leaves, and significantly up-regulated upon NaCl stress. The recombinant protein was heterologous expressed in Escherichia coli and exhibited a high level of UGT activity, catalyzing formation of isoliquiritin and liquiritin from isoliquiritigenin and liquiritigenin. The key residues of GuUGT2 for liquiritigenin glycosylation (Asn223), isoliquiritigenin (Asp272) were predicted by molecular docking and residue scanning based on simulated mutations. These results could serve as an important reference to understand the function of the UGT family. In addition, the identification of GuUGT2 and GuUGT3 provides a foundation for future studies of flavonoid biosynthesis in G. uralensis.

Global fishery resources have been declining for decades, leading some fisheries to collapse. Although the decline is partly due to man-made chemical contamination, causal chemicals have been identified in only a few cases. We conducted consecutive 3-year investigations of embryonic mortality in Taihu Lake, China, including heavily contaminated northern areas, including Zhushan (ZS), Meiliang (ML), and Gonghu (GH), and the less polluted southeastern Suzhou (SZ). In 2016, 65.8% of crucian carp (Carassius carassius) embryos collected from ZS died before hatching, a substantially higher mortality rate than those observed in ML (21.7%), GH (15.2%), and SZ (2.2%). In 2017, the embryonic mortality rates were 38.8% in ZS, 1.3% in ML, 6.9% in GH, and 3.5% in SZ, and these rates strongly correlated with the concentrations of tris(1,3-dichloro-2-propyl)phosphate (TDCIPP): 104.2, 1.8, 4.6, and 4.1 ng/g lipid weight (lw) in embryos from ZS, ML, GH, and SZ, respectively. In 2018, embryonic mortality decreased to 4.0% in ZS and 1.2% in GH, consistent with decreases in embryonic TDCIPP concentrations to 17.1 and 1.5 ng/g lw, respectively. Moreover, the TDCIPP concentrations in dead embryos (70.5-216.8 ng/g lw) were much higher than those in live embryos (1.2-10.5 ng/g lw). Embryonic mortality was also observed in well-controlled laboratory experiments in which wild crucian carp were exposed to TDCIPP at concentrations similar to those measured in embryos collected from Taihu Lake, thus confirming TDCIPP as a causal factor in mass crucian carp embryo mortality in Taihu Lake. TDCIPP thus poses a threat to the sustainability of fisheries worldwide, given the high worldwide production volume of this chemical and its embryonic lethal toxicity.

Family with sequence similarity 83 (FAM83) members were shown recently to have oncogenic effect in a variety of cancer types, but the biological roles and prognostic value of FAM83 family in pancreatic ductal adenocarcinoma remain unknown. In the current study, the clinical significance and molecular function of the FAM83 family were assessed by multiple bioinformatics analysis. Besides, potential associations between differentially expressed genes (DEGs) of FAM83 family and antitumor immunity were evaluated using TIMER and TISIDB analyses. As the results show, FAM83A, FAM83D, FAM83E, and FAM83H were significantly upregulated in PDAC and were identified as DEGs. Higher expression of FAM83A, FAM83B, FAM83D, FAM83E, and FAM83H were associated with advanced tumor stage or worse patient prognosis. Importantly, the overexpression of DEGs was found to be significantly correlated with activated KRAS and loss of SMAD4, which are important drivers for PDAC. Further, FAM83A, FAM83D, and FAM83H were associated with CD8+ T cell, Gamma Delta T cell, and CD4+ T cell infiltration in PDAC and FAM83H was found closely correlated with some immunomodulators including immunoinhibitors, immunostimulators, and MHC molecules. In conclusion, FAM83A, FAM83D, FAM83E, and FAM83H have significant prognostic value in PDAC and they may play important roles in regulating tumor progression and the immune cell infiltration.

Background: Recent evidence has shown that CKLF-like MARVEL transmembrane domain containing 3 (CMTM3) promoted carcinogenesis and tumor progression in a variety of cancer types. The goal of our study is to investigate the association between CMTM3 and pancreatic cancer (PC). Materials and Methods: In current study, data from public databases was used to analyze CMTM3 expression in PC. Quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC) were used to investigate CMTM3 expression and determine its clinical significance in PC. Then CMTM3 promoting PC aggressiveness was demonstrated in vitro experiments by cell proliferation and migration assay. Functional and pathway enrichment analyses were performed to evaluate the potential role of CMTM3 in PC. Results: Results of qRT-PCR and IHC revealed that CMTM3 was significantly overexpressed in PC tissues. High CMTM3 expression was an independent risk factor for poor prognosis of PC patients. Overexpression of CMTM3 was associated with poor overall survival (P-value =0.031) and disease-free survival (P-value =0.0047) in the TCGA cohort. Functional and pathway enrichment analyses showed that CMTM3 were enriched in “Regulation of cell proliferation and regulation of cell differentiation, cell morphogenesis, regulation of cell differentiation, Hedgehog signaling pathway, Wnt signaling pathway, ECM-receptor interaction and pathways in cancer”. In PC cell lines, CCK8, clone formation and transwell assays showed that CMTM3 knockdown inhibited cells proliferation and migration. Conclusion: CMTM3 was overexpressed and promotes tumor aggressiveness in PC. Our findings provided a novel therapeutic target for PC.

Objective Myricetin 3-O-galactoside is an active compound with pharmaceutical potential. The insufficient supply of this compound becomes a bottleneck in the druggability study of myricetin 3-O-galactoside. Thus, it is necessary to develop a biosynthetic process for myricetin 3-O-galactoside through metabolic engineering. Methods Two genes OcSUS1 and OcUGE1 encoding sucrose synthase and UDP-glucose 4-epimerase were introduced into BL21(DE3) to reconstruct a UDP-D-galactose (UDP-Gal) biosynthetic pathway in Escherichia coli. The resultant chassis strain was able to produce UDP-Gal. Subsequently, a flavonol 3-O-galactosyltransferase DkFGT gene was transformed into the chassis strain producing UDP-Gal. An artificial pathway for myricetin 3-O-galactoside biosynthesis was thus constructed in E. coli. Results The obtained engineered strain was demonstrated to be capable of producing myricetin 3-O-galactoside, reaching 29.7 mg/L. Conclusion Biosynthesis of myricetin 3-O-galactoside through engineered E. coli could be achieved. This result lays the foundation for the large-scale preparation of myricetin 3-O-galactoside.

Liquiritigenin (LG), isoliquiritigenin (Iso-LG), together with their respective glycoside derivatives liquiritin (LN) and isoliquiritin (Iso-LN), are the main active flavonoids of Glycyrrhiza uralensis, which is arguably the most widely used medicinal plant with enormous demand on the market, including Chinese medicine prescriptions, preparations, health care products and even food. Pharmacological studies have shown that these ingredients have broad medicinal value, including anti-cancer and anti-inflammatory effects. Although the biosynthetic pathway of glycyrrhizin, a triterpenoid component from G. uralensis, has been fully analyzed, little attention has been paid to the biosynthesis of the flavonoids of this plant. To obtain the enzyme-coding genes responsible for the biosynthesis of LN, analysis and screening were carried out by combining genome and comparative transcriptome database searches of G. uralensis and homologous genes of known flavonoid biosynthesis pathways. The catalytic functions of candidate genes were determined by in vitro or in vivo characterization. This work characterized the complete biosynthetic pathway of LN and achieved the de novo biosynthesis of liquiritin in Saccharomyces cerevisiae using endogenous yeast metabolites as precursors and cofactors for the first time, which provides a possibility for the economical and sustainable production and application of G. uralensis flavonoids through synthetic biology., Graphical abstract Liquiritigenin, isoliquiritigenin and their glycoside compounds liquiritin and isoliquiritin, the main active flavonoids of Glycyrrhiza uralensis, were de novo heterologously synthesized in Saccharomyces cerevisiae by using raw materials and cofactors from the endogenous metabolic system of yeast.Image 1

The humpback grouper (Cromileptes altivelis) is a commercially valuable species of the family Epinephelidae; however, its marketization suffers from slow growth speed, low survival rate, and various pathogenic diseases. Lactococcus lactis and Schizochytrium limacinum are commonly used as immunostimulants due to their health benefits for the aquatic organisms. In the present study, we assessed the effects of dietary supplementation with L. lactis HNL12 combined with S. limacinum algal meal on the growth performances, innate immune response, and disease resistance of C. altivelis against Vibrio harveyi. The results showed that fish fed with a combination diet of L. lactis and S. limacinum exhibited significantly higher final weight, percent weight gain, and specific growth rate compared with groups fed with them alone. A bacterial challenge experiment indicated that the group fed with the L. lactis combined with S. limacinum diet achieved the highest relative percent of survival value (68.63%), suggesting that L. lactis and S. limacinum significantly improved the disease resistance against V. harveyi after a 4-week feeding trial. Moreover, the respiratory burst activity of macrophages of fish fed with a L. lactis combined with S. limacinum diet was significantly higher than that of fish fed the control diet after 1, 2, and 3 weeks of feeding. The serum superoxide dismutase of fish fed with a L. lactis combined with S. limacinum diet significantly increased compared to those fed the control diet after 1 and 2 weeks of feeding, while the serum alkaline phosphatase of fish fed with a L. lactis combined with S. limacinum diet after 2 and 4 weeks was significantly increased, compared to the control group. The serum lysozyme activities of fish fed with a L. lactis combined with S. limacinum diet significantly increased compared to the control group after 2 weeks of feeding. Furthermore, transcriptome sequencing of the C. altivelis head kidney was conducted to explore the immune-regulating effects of the L. lactis combined with S. limacinum diet on C. altivelis. A total of 86,919 unigenes, annotated by at least one of the reference databases (Nr, Swiss-Prot, GO, COG, and KEGG), were assembly yielded by de novo transcriptome. In addition, 157 putative differentially expressed genes (DEGs) were identified between the L. lactis combined with S. limacinum group and the control group. For pathway enrichment, the DEGs were categorized into nine KEGG pathways, which were mainly related to infective diseases, antigen processing and presentation, digestive system, and other immune system responses. The findings of this study suggest that the L. lactis combined with S. limacinum diet can induce positive effects on the growth, immunity, and disease resistance of C. altivelis against V. harveyi. This study expands our understanding of the synergistic combinations of probiotics and prebiotics in aquaculture.

Giant clams are found in a mutualistic association with Symbiodiniaceae dinoflagellates, however, the diversity of the giant clams, as well as the diversity and distribution of Symbiodiniaceae in different Tridacnine species remain relatively poorly studied in the South China Sea. In this study, a total of 100 giant clams belonging to small type’s giant clams, Tridacna maxima, T. crocea, and T. noae, were collected from Hainan and Xisha Islands. Based on mtDNA cytochrome c oxidase subunit 1 gene (COI) and 16S rRNA fragments, T. maxima and T. crocea showed a closer phylogenetic relationship than T. noae. All the three species of giant clams hosted Symbiodiniaceae including genera Symbiodinium (formerly Clade A) and Cladocopium (formerly Clade C). Geographically, symbionts in Cladocopium are restricted to Xisha Islands, probably because Cladocopium prefers to inhabit in waters with higher mean temperatures. The endosymbiont specificity among the three giant clam species was also detected. T. noae and T. crocea are found to harbor Symbiodinium preferentially, compared with Cladocopium. These results could provide important information to understand various endosymbionts occurring in giant clams in the South China Sea.

Pearl oyster (Pinctada fucata martensii) is the main species cultured for marine pearls in the world. A breeding program was carried out for desirable production traits, including high growth rate, and a fast-growing selective strain of pearl oysters was established. In the current study, we compared the growth characteristics between a selective strain and a cultured population of P. f. martensii in Beihai, Guangxi Province, China. Large size (SL) and small size (SS) individuals of the selective strain were selected, and the differences of physiological and metabolic indexes, such as feeding, respiration, excretion, and enzyme activities between SL and SS and cultured population (CL), were also compared. The results showed that at the age of 6 months, pearl oysters of the selective strain were 14.61% larger than CL, and the proportion of SL (30–40 mm) was 59%, which was two times higher than CL (28%). SL with a rapid growth rate had a high clearance rate (CR), and the CR of SL was about 1.8 times higher than that of CL and 5 times higher than that of SS. In addition, the activities of digestive enzymes (amylase, pepsin, and lipase) and growth-related carbonic anhydrase enzymes in SL were higher than those in the other two groups (p < 0.05). SS with a slow growth rate had higher oxygen consumption (OCR) and ammonia excretion (AER) rates than SL and CL (p < 0.05). Our results suggest that the rapid growth of the selective strain P. f. martensii can be attributed to increased energy intake and reduced energy consumption.

Glycyrrhetic acid 3-O-mono-β-D-glucuronide (GAMG) is a rare compound in licorice and its short supply limits the wide applications in the pharmaceutical, cosmetic, and food industries. In this study, de novo biosynthesis of GAMG was achieved in engineered Saccharomyces cerevisiae strains based on the CRISPR/Cas9 genome editing technology. The introduction of GAMG biosynthetic pathway resulted in the construction of a GAMG-producing yeast strain for the first time. Through optimizing the biosynthetic pathway, improving the folding and catalysis microenvironment for cytochrome P450 enzymes (CYPs), enhancing the supply of UDP-glucuronic acid (UDP-GlcA), preventing product degradation, and optimizing the fermentation conditions, the production of GAMG was increased from 0.02 μg/L to 92.00 μg/L in shake flasks (4,200-fold), and the conversion rate of glycyrrhetic acid (GA) to GAMG was higher than 56%. The engineered yeast strains provide an alternative approach for the production of glycosylated triterpenoids.

BackgroundThe glycyrrhizic acid biosynthesis pathway does not exist in isolation, but is connected with the biosynthesis pathways of other secondary metabolites in licorice and finally forms a network. Our previous study found that exogenous spraying of appropriate concentration of abscisic acid (ABA) could increase the content of glycyrrhizic acid (GA) in licorice. However, the mechanism of action remains unknown. We aim to understand the molecular mechanism of ABA promoting the synthesis of GA in licorice and find the molecular marker for the high content of GA germplasm material.MethodsWe analyzed the expression of the key gene of β-AS for GA synthesis after applying ABA, the key functional genes NCED1, NCED3 and NCED4 in the process of ABA synthesis were overexpression, and analyzed the relationship between the SNP polymorphism of the NCED1, NCED3, NCED4 and the content of the GA and ABA in 13 different provenances of licorice with the grey correlation analysis. ResultsThe appropriate concentration of ABA treatment could increase the content of the GA through improving the expression of β-AS. There were significant differences in the content of ABA and GA among the 13 provenances, and the 3 members of the NCEDs family of different provenances had abundant SNP variation sites. Grey correlation and overexpression of NCEDs function both showed that the effect of promoting the synthesis of ABA and GA: NCED1 437 bp G type > NCED3 966 bp G type > NCED4 845 bp A type. All of the above indicated that NCEDs gene variation was the reason for the diversity of GA and ABA content. When selecting high GA germplasm, more priority should be given to NCED1 gene 437 bp G type, NCED3 gene 966 bp G type and NCED4 gene 845 bp A type. ConclusionThis study provides a basis for the selection of excellent GA content germplasm of licorice, and provide some reference for producing a high quality cultivated licorice.

The method of drying licorice is an important factor affecting the quality of the final product. To determine the best processing method of licorice postharvest, we investigated the interaction of increasing aridity between the endophytic microorganisms and the accumulation of metabolites. Samples from the roots of licorice growing along an aridity gradient during the natural drying process were collected, and the metabolic components, the content of the main active substances and the dynamic changes of the endophytic microbial community were assessed. The glycyrrhizic acid and liquiritin contents decreased slightly or remained flat during natural drying, whereas those of liquiritigenin and isoliquiritigenin increased slightly. Moreover, the Shannon index of endophytic microbial diversity of licorice was the highest in the fresh period and showed a downward trend during the drying process. When the licorice were fresh, Cladosporiaceae and Burkholderiaceae were the dominant family present, but after drying, Nectriaceae and Enterobacteriaceae were the dominant families. A similar trend was also found in which the differential metabolites of licorice were reduced during natural drying. Furthermore, correlation analysis between dominant families and differential metabolites showed that there was a correlation between the two. Therefore, fresh processing is an effective drying method to ensure the quality of licorice. This study revealed the relationship of endophytic microbiota and changes in the licorice metabolites during different stages of drying, which provided a scientific basis for the drying method of licorice.

The color of aquatic animals plays an important role in consumer acceptability and perceived quality. In a previous study, a red claw crayfish Cherax quadricarinatus strain with steady and hereditary shell color of blue was selected. To evaluate the potential value of this strain in crayfish culture, the growth performance, carotenoid content, and temperature tolerance of two crayfish strains (shell color; blue and blue-green) were conducted. After the 56-day rearing period, blue crayfish showed higher feed intake and growth rate, but lower survival than blue-green crayfish. Astaxanthin was the main pigment observed in the carapace of both strains, and the content of astaxanthin in blue crayfish was 18.62 mg/kg of wet weight, which was significantly lower than that of astaxanthin in blue-green crayfish (83.23 mg/kg of wet weight). The 7-day survival of two crayfish strains less than 34°C was 100%, and blue-green crayfish showed stronger tolerance to high water temperature exposure (35°C–38°C) than blue crayfish. Furthermore, after high temperature stress, lower activities of superoxide dismutase and catalase, and higher malondialdehyde in the hepatopancreases of blue crayfish were observed than those in blue-green crayfish. This study provides important information for future breeding programs for the red claw crayfish.

Genetic diversity is the raw material for germplasm enhancement. Landraces and wild species relatives of potato, which contain a rich gene pool of valuable agronomic traits, can provide insights into the genetic diversity behind the adaptability of the common potato. The diploid plant, Solanum stenotomum (Sst), is believed to have an ancestral relationship with modern potato cultivars and be a potential source of resistance against disease. Sequencing of the Sst genome generated an assembly of 852.85 Mb (N50 scaffold size, 3.7 Mb). Pseudomolecule construction anchored 788.75 Mb of the assembly onto 12 pseudochromosomes, with an anchor rate of 92.4%. Genome annotation yielded 41,914 high-confidence protein-coding gene models and comparative analyses with closely related Solanaceae species identified 358 Sst-specific gene families, 885 gene families with expansion along the Sst lineage, and 149 genes experiencing accelerated rates of protein sequence evolution in Sst, the functions of which were mainly associated with defense responses, particularly against bacterial and fungal infection. Insights into the Sst genome and the genomic variation of cultivated potato taxa are valuable in elaborating the impact of potato evolution in early landrace diploid and facilitate modern potato breeding.

Arnebia decumbens (Vent.) Coss. et Kralik, A. euchroma (Royle) Johnst and A. guttata Bunge, three commonly used traditional Chinese medicinal plants have been widely used for the clinical treatment of inflammatory diseases caused by fungal, bacterial, oxidation, and other related pathogens. However, precise identification at the similar species level is usually challenging due to the influence of the source of medicinal materials, traditional ethnic medicine and medicinal habits. Here we developed a comprehensive and efficient identification system for three source spices of Arnebiae Radix based on DNA barcoding and HPLC fingerprinting. A total of 599 samples from thirty-five wild populations were collected and identified by using DNA barcodes of ITS2 regions, and the chemotypes of seven naphthoquinoneswere revealed by HPLC quantitative analysis including principal component analysis and hierarchical clustering analysis. Our results showed that the ITS2 sequences can distinguish three source spices of Arnebiae Radix from adulterants. However, it was difficult to identify them by HPLC-specific chromatograms combined with chemometric analysis. These results indicated that DNA barcoding was a more powerful method than HPLC fingerprinting for the identification of related species that were genetically similar. DNA barcoding analysis could be a promising and reliable tool to accurately confirm the identities of medicinal materials, especially for those whose sources are multiple and difficult to be identified by conventional chromatography.

Tris(1,3-dichloro-2-propyl)phosphate (TDCIPP) has commonly been used as an additive flame retardant and frequently detected in the aquatic environment and in biological samples worldwide. Recently, it was found that exposure to TDCIPP inhibited the growth of zebrafish, but the relevant molecular mechanisms remained unclear. In this study, 5 day-old crucian carp (Carassius auratus) larvae were treated with 0.5, 5, or 50 μg/L TDCIPP for 90 days; the effect on growth was evaluated; and related molecular mechanisms were explored. Results demonstrated that 5 or 50 μg/L TDCIPP treatment significantly inhibited the growth of crucian carp and downregulated the expression of growth hormones (ghs), growth hormone receptor (ghr), and insulin-like growth factor 1 (igf1). Molecular docking, dual-luciferase reporter gene assay, and in vitro experiments demonstrated that TDCIPP could bind to the growth hormone releasing hormone receptor protein of crucian carp and disturb the stimulation of growth hormone releasing hormone to the expression of ghs, resulting in the decrease of the mRNA level of gh1 and gh2 in pituitary cells. Our findings provide new perceptions into the molecular mechanisms of developmental toxicity of TDCIPP in fish.

The effects of high hydrostatic pressure (HHP) processing at 200 MPa, 400 MPa, and 600 MPa on the proximate composition, inactivation of bacteria, and color of the red claw crayfish Cherax quadricarinatus were evaluated. High hydrostatic pressure processing resulted in complete shelling and a significant decrease in the moisture content (P < 0.05), whereas no significant differences were observed in the content of ash, crude protein, and crude lipid, except for the crude lipid content between 200 MPa and 600 MPa groups (P < 0.05). After pressurization, the Escherichia coli, Vibrio vulnificus, and Vibrio parahaemolyticus counts decreased significantly with the increase of pressure, even to an undetected level for V. vulnificus and V. parahaemolyticus at 400 and 600 MPa (P < 0.05), respectively. During 30-d storage at 4°C and –20°C, the counts of these three bacterial species increased significantly with increased storage time and temperature. After HHP processing, a* value changed substantially, whereas L* and b* values had little change for meat. The total color difference (ΔE*) suggested that the HHP-treated red claw crayfish exhibited very distinctive or substantial differences compared with fresh individuals.

Giant clams Tridacna crocea harbor symbiotic zooxanthellae in tubular systems and display high growth rate when exposed to light. Light/dark alternation plays an important role in growth performance and physiological change of giant clam–zooxanthellae symbiosis in natural ecosystems. In this study, photosynthetic performance, antioxidant enzymes, transcriptome, and expression of eight illumination-related genes were investigated in the mantle of giant clam at different treatment times of 12-h light/12-h dark (15,000 lx). (1) The effective photochemical quantum yield of PSII (Y(II)) was high in the early morning, but significantly decreased to a low level at 6 h of light treatment (P

There has been an increasing incidence rate of rice false smut in global rice cultivation areas. However, there is a dearth of studies on the environmental concentrations and hazards of ustiloxin A (UA), which is the major mycotoxin produced by a pathogenic fungus of the rice false smut. Here, the concentrations of UA in the surface waters of two paddy fields located in Enshi city, Hubei province, China, were measured, and its toxicity in T. Thermophila was evaluated. This is the first study to detect UA in the surface waters of the two paddy fields, and the measured mean concentrations were 2.82 and 0.26 μg/L, respectively. Exposure to 2.19, 19.01 or 187.13 μg/L UA for 5 days significantly reduced the theoretical population and cell size of T. thermophila. Furthermore, treatment with 187.13 μg/L UA changed the percentages of T. thermophila cells in different cell-cycle stages, and with an increased malformation rate compared with the control, suggesting the disruption of the cell cycle. The expressions of 30 genes involved in the enriched proteasome pathway, 7 cyclin genes (cyc9, cyc10, cyc16, cyc22, cyc23, cyc26, cyc33) and 2 histone genes (mlh1 and hho1) were significantly down-regulated, which might be the modes of action responsible for the disruption of cell cycling due to UA exposure.

Ustiloxin A is a cyclopeptide mycotoxin originally isolated from rice false smut balls (FSBs) that formed in rice spikelets infected by the fungal pathogen Ustilaginoidea virens. Studies have shown that ustiloxin A was toxic to animals, but the toxicological evidence is still lacking. To reveal the negative influence of ustiloxin A on model organism, zebrafish were selected and exposed to ustiloxin A at concentrations of 0, 0.25, 2.5 or 25 μM from 2 h post-fertilization (hpf) to 144 hpf. The hatching rates of embryos in the 25 μM exposure group was 12.85% less than the control group at 96 hpf. Meanwhile, exposure to 0.25, 2.5 or 25 μM ustiloxin A resulted in a distinct dose-dependent increase in mortality rate of embryos at 96 hpf. We also found that exposed to ustiloxin A could cause some other damages on zebrafish larvae, such as growth delay and increased heart rate. In addition, the athletic behavior of zebrafish larvae exposed to ustiloxin A at 25 μM was dramatically different with that of control. Transcriptome sequencing showed that abundances of 339 transcripts (125 up-regulated and 214 down-regulated) were significantly altered in larvae exposed to 25 μM of ustiloxin A. Several of the crucial genes were validated by RT-qPCR. This is the first report on the toxicologic study of ustiloxins against model organism zebrafish. Results suggested that ustiloxins have become a potential danger for food security.

CC chemokines are a large subfamily of chemokines that play an important role in the innate immune system. To date, several CC chemokines have been identified in fish species; however, the activities and functions of these putative chemokines remain ambiguous in teleosts, especially in the golden pompano, Trachinotus ovatus. Here, we characterized CC chemokine ligand 4 from T. ovatus (TroCCL4) and studied its functions. TroCCL4 contains a 294 bp open reading frame that encodes a putative peptide comprising 97 amino acids. TroCCL4 shares a high amino acid sequence similarity of 31.11%-78.35% with other CC chemokines sequences in humans and teleosts and has four cysteine residues that are conserved among other CC chemokines. TroCCL4 is also related to the macrophage inflammatory protein (MIP) group of CC chemokines. TroCCL4 expression was most abundant in immune organs and significantly upregulated in a time-dependent manner following Edwardsiella tarda infection. Recombinant TroCCL4 (rTroCCL4) induced the migration of peripheral blood leukocytes and the cellular proliferation of head kidney lymphocytes. In addition, rTroCCL4 inhibited the growth of Escherichia coli and E. tarda, indicating an antimicrobial function. Furthermore, the results of in vivo analysis showed that TroCCL4 overexpression in T. ovatus significantly enhanced macrophage activation; upregulated the gene expression of interleukin 1-β (IL-1β), interleukin 15 (IL15), interferon-induced Mx protein (Mx), tumor necrosis factor α (TNFα), complement C3, and major histocompatibility complex (MHC) class Iα and class IIα; and protected against bacterial infection in fish tissues. In contrast, knockdown of TroCCL4 expression resulted in increased bacterial dissemination and colonization in fish tissues. Taken together, our results provide evidence indicating that TroCCL4 has the ability to stimulate leukocytes and macrophages and enhance host immunity to defend against bacterial infection.

Recently, several studies showed that microcystin-LR (MCLR) can accumulate and induce toxicity in kidney. However, the exact mechanism is unknown. The aim of this study was to explore the mechanism of MCLR-induced nephrotoxicity. To this end, adult zebrafish were exposed to MCLR (0, 1, 5 and 25 μg/L) for 60 days. Exposure to MCLR caused histopathological lesions, which were characterized by renal tubules filled with eosinophilic casts, abnormal renal tubules, intertubular space decrease, and blood infiltration in renal cells. RNA-Seq analysis indicated that exposure to MCLR significantly interfered with renal gene expressions, and these genes were enriched in various pathways, such as oxidative phosphorylation, cell cycle, and protein processing in endoplasmic reticulum, which were related to apoptosis. Furthermore, terminal deoxynucleotide transferase-mediated deoxy-UTP nick end labelling (TUNEL) assay showed that MCLR exposure induced renal cell apoptosis. In addition, negative changes of the reactive oxygen species (ROS) level as well as apoptotic-related gene, protein expressions and enzyme activities suggested that MCLR could induce production of ROS, subsequently triggering apoptosis via p53-bcl-2 and caspase-dependent pathway in the kidney of zebrafish. Therefore, it can be concluded that apoptosis is a primary case of MCLR-induced nephrotoxicity.

Maternal transfer toxicity of chemicals has mainly focused in fish on the chemical transfer from maternal generation to offspring, and limited information is available for the evaluation of effects of chemicals from a biological transfer perspective. In this study, first-generation (F0) zebrafish larvae (D. rerio) were exposed to 0, 50, 500 or 5000 ng/L TDCIPP from 14 days post fertilization (dpf) to 120 dpf. F0-generation zebrafish were paired, and F1-generation embryos were collected and continuously exposed to the same concentrations of TDCIPP until 150 dpf. F1-generation females were then paired with unexposed adult males, and maternal transfer effects on survival rate and body length were evaluated. Results demonstrated that maternal exposure to TDCIPP for two generations significantly decreased body length of F2-generation larvae, suggesting the occurrence of maternal transfer toxicity. The transfer of TDCIPP from maternal generation to offspring was evident, but microinjection of equal amounts of TDCIPP did not affect survival and body length of zebrafish larvae. Furthermore, maternal exposure to TDCIPP changed the concentrations of partial mRNAs and proteins in their eggs, and those changes were linked to maternal transfer toxicity (e.g., growth inhibition). These results suggested that in zebrafish changes in biological transfer may explain, at least in part, the observed maternal transfer toxicity of TDCIPP.

Lactic acid bacteria are a common group of probiotics that have been widely studied and used in aquaculture. In the present study, we isolated Lactococcus lactis HNL12 from the gut of wild humpback grouper (Cromileptes altivelis) and explored its probiotic properties. For this purpose, L. lactis HNL12 was added to the commercial fish feed. The results showed that HNL12 had high auto-aggregation ability and strong tolerance to simulated gastrointestinal stress. When C. altivelis consumed a diet containing 0 (control), 106, 108, or 1010 CFU/g HNL12 for four weeks, all of the groupers fed a diet with HNL12 had significantly increased percent weight gain (PWG), especially those fed with 108 CFU/g, which had a PWG of 231.45%. Compared to the control, fish fed with L. lactis HNL12 exhibited significantly increased survival rates following injection with Vibrio harveyi after one month. Immunological analysis showed that C. altivelis fed with HNL12 had (i) enhanced respiratory burst activity of head kidney macrophages, superoxide dismutase, acid phosphatase, and lysozyme activities of serum; (ii) an improved survival rate from 36% to 70%; and (iii) upregulated expression of a broad spectrum of immunity. Meanwhile, de novo transcriptome assembly yielded 89,314 unigenes, which were annotated by at least one of the reference databases (Nr, Swiss-Prot, GO, COG and KEGG). A total of 307 genes showed significantly different expression between the groups fed with or without added HNL12. GO and KEGG enrichment analyses of the significantly different expression gene categories and pathways were related to infectious diseases, antigen processing and presentation, and other immune system responses. These results indicate that L. lactis HNL12 is effective for enhancing the growth, immunity, and disease resistance of C. altivelis; this study also provides insight into the use of probiotics for commercial applications.

There is sparse information about the evaluation of the effects on ova of estrogen inhibition in fish. In this study, two exposure experiments were performed. First, adult zebrafish were exposed to...

Perfluorododecanoic acid (PFDoA), an artificial perfluorochemical, has been widely distributed in different ambient media and has been reported to have the potential to cause developmental neurotoxicity. However, the specific mechanism is largely unknown. In the current study, zebrafish embryos were treated with 0, 0.24, 1.2, and 6 mg/L PFDoA for 120 h. Exposure to PFDoA causes serious decreases in hatching delay, body length, as well as decreased locomotor speed in zebrafish larvae. Additionally, the acetylcholine (ACh) content as well as acetylcholinesterase (AChE) activity were determined to be significantly downregulated in PFDoA treatment groups. The level of dopamine was upregulated significantly after treating with 1.2 and 6 mg/L of PFDoA. Gene expressions related to the nervous system development were also analyzed, with the exception of the gene mesencephalic astrocyte-derived neurotrophic factor (manf), which is upregulated in the 6 mg/L treatment group. All other genes were significantly downregulated in larvae in the PFDoA group in different degrees. In general, the results demonstrated that PFDoA exposure could result in the disruption of the cholinergic system, dopaminergic signaling, and the central nervous system.

The major objective of this study was to evaluate the inhibitory effect of essential oil (EO) from Zanthoxylum armatum DC. on Aspergillus flavus. The chemical composition of the EO was identified by gas chromatography–mass spectrometer. The minimum inhibitory concentration (MIC) of EO was investigated by liquid fermentation. The morphology, colony number, and aflatoxin content of A. flavus in platycladi semen were investigated by stereomicroscopy, scanning electron microscopy, plate counting, and high-performance liquid chromatography. The results indicated that the MIC of EO was 0.8 μL⋅mL–1, and the main components were β-phellandrene (7.53%), D-limonene (13.24%), linalool (41.73%), terpinen-4-ol (5.33%), and trans-nerolidol (6.30%). After the EO fumigated the platycladi semen, the growth of A. flavus slowed, and the mycelium shrank considerably. The number of colonies after EO treatment at room temperature and cold storage was significantly reduced, the inhibition effect was better under cold storage, and the aflatoxin B1 content did not exceed the standard within 100 days. Therefore, this study demonstrated the good potential of A. flavus growth inhibition during the storage of platycladi semen.

Contamination with heavy metals in wild red swamp crayfish (Procambarus clarkii) from 7 different geographical areas in six provinces of China (Hubei, Hunan, Jiangxi, Anhui, Jiangsu, and Shandong) was evaluated. Concentrations of chromium (Cr), arsenic (As), lead (Pb), cadmium (Cd), and mercury (Hg) in the abdominal muscle, gonad, and hepatopancreas were determined by inductively coupled plasma mass spectrometry (ICP-MS) and Atomic Fluorescence Spectrometer (AFS). Except for the Cd content in hepatopancreas, the contents of selected heavy metals in three different tissues were significantly lower than the proposed limits provided by United States Environmental Protection Agency (USEPA). The maximum accumulations of Cd and Pb were in hepatopancreas, while the maximum accumulation of As was in gonad, and the maximum accumulations of Hg and Cr were in abdominal muscle. The highest contents of Cr, Hg, and Pb were all detected in Dongting Lake, Hunan, which was consistent with the trend of the metal pollution index (MPI). Risk value of the target hazard quotient (THQ) was below 1.0, suggesting that the intake of selected heavy metals through crayfish consumption would not pose a significant health risk to consumers.

The potential exposure of titanate nanotubes (TNTs) to wildlife and humans may occur as a result of increased use and application as functional nanomaterials. However, there is a dearth of knowledge regarding the pathways of uptake and excretion of TNTs and their toxicity in cells. In this study, three strains of the Tetrahymena genus of free-living ciliates, including a wild type strain (SB210) and two mutant strains (SB255: mucocyst-deficient; NP1: temperature-sensitive "mouthless''), were used to study the pathways of uptake and excretion and evaluate the cytotoxicity of TNTs. The three Tetrahymena strains were separately exposed to 0, 0.01, 0.1, 1 or 10 mg/L of TNTs, and cells were collected at different time points for quantification of intracellular TNTs (e.g., 5, 10, 20, 40, 60, 90 and 120 min) and evaluation of cytotoxicity (12 and 24 h). TNT contents in NP1 and SB255 were greater or comparable to the contents in SB210 while exposure to 10 mg/L TNTs in 120 min. Furthermore, exposure to 10 mg/L TNTs for 24 h caused greater decreases in cell density of NP1 (38.2 %) and SB255 (36.8 %) compared with SB210 (26.5 %) and upregulated the expression of caspase 15 in SB210. Taken together, our results suggested that TNT uptake by pinocytosis and excretion by exocytosis in Tetrahymena, and the exposure could cause cytotoxicity which can offer novel insights into the accumulation kinetics of nanotubes and even nanomaterials in single cell.

Limited studies were performed to evaluate the effects of bisphenol A (BPA) and bisphenol AF (BPAF) in low-trophic-level animals, such as Daphnia magna (D. magna). In this study, a 21-day standard reproductive toxicity test was carried out to assess the effects of the 2 bisphenols on development, reproduction, and transcription of genes in D. magna. The results demonstrated that only exposure to 5000 nM BPA significantly decreased the survival rate, while significant alternations were observed after exposure to 50, 500, or 5000 nM BPAF. Both the molting numbers of per female and body length of F0 generation were decreased after exposure to 500 nM BPAF, while no obvious effects were observed after treatment with lower concentrations of BPAF and BPA. Increased fecundity but decreased body length and swimming speed of F1 generation were observed after exposure to 5000 nM BPA or 500 nM BPAF. In addition, the results of the qRT-PCR showed the expressions of cyp314, ecra, ecrb, usp, vtg1, and vtg2 were significantly inhibited after exposure to 5000 nM BPA, while the expressions of cyp18a1 and vmo1 were obviously upregulated after exposure to 500 nM BPAF.

The effects of HHP and storage temperature on bacterial counts, color, fatty acids and flavor compounds of oysters Crassostrea ariakensis were investigated. Counts of Vibrio vulnificus and Vibrio parahaemolyticus decreased to undetectable levels in ≥ 400 MPa-treated oysters. Storage at -20 °C significantly restrained microbial growth compared to 4 °C (P 0.05). L* values of HHP-treated oysters significantly increased compared to raw oysters (P 0.05). Storage slightly affected the color according to total color difference (ΔE*) values. Fatty acid profiles and betaine contents in 400 and 600 MPa-treated oysters at 0 and 15 d were almost the same as raw samples. Contents of total free amino acids (FAAs), Na

This study explored the combined effects of titanium dioxide nanoparticles (nano-TiO2) and triphenyl phosphate (TPhP) on the neurodevelopment of zebrafish larvae as well as the underlying mechanisms. With this regard, zebrafish embryos were exposed to nano-TiO2 of 100 μg·L−1, TPhP of 0, 8, 24, 72, and 144 μg·L−1, or their combinations until 120 h post-fertilization (hpf). Results indicated 100 μg·L−1 nano-TiO2 alone to be nontoxic to zebrafish larvae. However, obvious developmental toxicity manifested as inhibition of surviving rate, heart rate and body length as well as increased malformation was observed in the higher concentrations of TPhP (72 and 144 μg·L−1) alone and the co-exposure groups. Additionally, results suggested that nano-TiO2 significantly enhanced the bioaccumulation of TPhP in zebtafish larvae, and thus aggravated the abnormities of spontaneous movement and swimming behavior in zebrafish larvae induced by TPhP. Nano-TiO2 also exacerbated the TPhP-induced inhibition of the axonal growth on the secondary motor neuron, and aggravated the TPhP-induced decrease on expressions of neuron-specific green fluorescent protein (GFP) and neuronal marker genes (ngn1 and elavl3). Further, the content of neurotransmitter serotonin was not altered by TPhP alone exposure, but was decreased significantly in the co-exposure group of 144 μg·L−1 TPhP and nano-TiO2. Our data indicated that nano-TiO2 might aggravate the neuron abnormities and serotonin system dysfunction by enhancing the TPhP accumulation, leading to exacerbated abnormal locomotors in zebrafish larvae.

Integrin β (ITGB) superfamily members have been reported to play important roles in multiple biological functions in various cancers. However, the prognostic and oncologic values of ITGB superfamily members have not been systematically investigated in pancreatic cancer (PC). In this study, the mRNA expression and biological functions of ITGB superfamily members in PC were evaluated by bioinformatic analysis. Our results demonstrated that ITGB1, ITGB4, ITGB5 and ITGB6 overexpressions were significantly associated with advanced AJCC stage and histologic grade, and worse prognosis in PC. A prognostic signature based on ITGB1, ITGB4, ITGB5 and ITGB6 showed a reliable predictive performance. Furthermore, one CpGs (cg20545410) in promoter region of ITGB1, four (cg18709893, cg15700850, cg20667796 and cg18326022) of ITGB4, two (cg10977398 and cg03518058) of ITGB5 and one (cg23008083) of ITGB6 were negatively associated with their corresponding mRNA expression, and positively associated with prognosis in PC. We also identified TFAP2A as the potential transcription factor for ITGB4, SP1 for ITGB1 and ITGB6, and FHL2 for ITGB5 and ITGB6. ITGB1, ITGB4, ITGB5 and ITGB6 overexpressions were all significantly involved in focal adhesion signalling pathway. ITGB1 and ITGB5 overexpressions also associated with up‐regulation of TGF‐β and WNT signalling pathway, whereas ITGB4 and ITGB6 overexpressions associated with up‐regulation of Notch signalling pathway. Besides, ITGB1, ITGB5 and ITGB6 overexpressions significantly correlated with immunosuppression in PC. In summary, our study investigated the multilevel prognostic and biological values of ITGB superfamily members in PC.

Fishery resources are highly threatened by man-made chemicals that cause early life-stage mortality in fish, and could consequently block population recruitment. In a wide-scale and long-term investigation in Taihu Lake, we found that the temporal and spatial variation in embryonic mortality of crucian carp were consistent with the embryonic TDCIPP concentrations. We also confirmed in a well-controlled laboratory study that environmental concentrations of TDCIPP could cause embryonic mortality in crucian carp. Thus, TDCIPP was a major causal agent for mass embryonic mortality of crucian carp in Taihu Lake. These findings highlight the deleterious effect of this high-production-volume industrial chemical on global fishery and suggest ecosystem conservation should account for supervision of ubiquitous chemicals.

As a common organophosphorus flame retardant, tris (2-butoxyethyl) phosphate (TBOEP) is detected in water environment and aquatic animals extensively. Despite previous researches have reported the developmental toxicity of TBOEP in zebrafish (Danio rerio) larvae, few research focused on its underlying mechanisms. In this study, zebrafish embryos were exposed to 0, 20, 200, 1000 and 2000 µg/L TBOEP from 2 until 120 h post-fertilization (hpf) to determine potential mechanisms of developmental toxicity of this compound. Early developmental stage parameters such as body length, survival rate, hatching rate and heart rate were decreased, while malformation rate was ascended. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay was carried out at 12, 24, 72 and 120 hpf to demonstrate alterations in expression of genes of Wnt signaling pathway. The results indicated that axin1 was significantly up-regulated, while β-catenin, pkc and wnt11 were down-regulated. Correlation analysis indicated that expression of these genes was significantly correlated with body length. Furthermore, apoptosis was detected in heart region by acridine orange (AO) staining and terminal deoxynucleotide transferase-mediated deoxy-UTP nick end labeling (TUNEL) assay. In addition, at 120 hpf, occurrence of oxidative stress was observed in zebrafish larvae. Moreover, 6-Bromoindirubin-3′-oxime (BIO)， an activator of Wnt pathway, was found to alleviate the inhibiting effects of TBOEP on zebrafish growth. The overall outcomes offered novel viewpoints in toxic effects of TBOEP, and down-regulating Wnt signaling pathway were able to reveal some potential mechanisms of developmental toxicity of TBOEP in zebrafish larvae.

Triphenyl phosphate (TPHP) is one of the most widely used organophosphate flame retardants (OPFRs) and is frequently detected in a variety of environmental media. Previous studies reported that TPHP had toxic effects on vertebrates, but little toxic information was available in lower trophic aquatic organisms which were more sensitive to the exposure of many toxic substances. In this study, protozoa Tetrahymena thermophila (T. thermophila) were exposed to 0, 0.01, 0.17 or 2.35 mg/L TPHP for 5 days to study the effects of sub-chronic exposure on theoretical population, cell viability, cell size and number of cilia. Additionally, the effects of TPHP on gene transcription were assessed by transcriptome sequencing technique (RNA-Seq). Cell viability and number of cilia were significantly reduced in all TPHP exposure groups compared with the control. In addition, exposure to 0.17 or 2.35 mg/L TPHP significantly reduced the theoretical population, circumference and body width, and there was a significant decrease in body length in the 2.35 mg/L exposure group. Comparative transcriptome sequencing identified a total of 4105 up- and 4487 down-regulated genes after exposure to 2.35 mg/L TPHP for 5 days compared with the control. KEGG analysis showed that dysfunction of pathways associated with ribosome, spliceosome, phagosome, proteasome and protein processing in endoplasmic reticulum in this study might be responsible for the toxicity of T. thermophila caused by TPHP. In general, the results indicated that TPHP had an adverse effect on the protozoa T. thermophila.

Coronavirus disease 2019 (COVID‐19) caused by the severe acute respiratory syndrome coronavirus 2 has become an important public health issue in the world. More than 118 000 cases were confirmed around the world. The main clinical manifestations were respiratory symptoms and occasional gastrointestinal symptoms. However, there is no unified standard for the diagnosis and treatment of COVID‐19. In the retrospective analysis, we report nine cases of COVID‐19, describe the history of contact, clinical manifestations, the course of diagnosis and clinical treatment before, during and after treatment., Highlights In all, this study provides valuable information for clinical diagnosis and treatment of COVID‐19.

Insulin-like growth factor binding protein 3 (IGFBP3), an important member of the IGFBP family, plays an important biological role in regulating cellular proliferation, differentiation, growth, apoptosis, and innate immunity. However, studies concerning IGFBP3 in teleosts are very limited and IGFBP3 function remains unclear. In this study, we conducted both in vivo and in vitro functional analyses of an IGFBP3 (TroIGFBP3) from the teleost fish golden pompano (Trachinotus ovatus). TroIGFBP3 is composed of 286 amino acid residues and shares a high amino acid sequence similarity (50.18%-93.71%) with other IGFBP3 sequences in humans and teleosts. TroIGFBP3 was widely distributed in various tissues, with the highest expression in the liver. TroIGFBP3 expression was significantly upregulated following Vibrio harveyi infection. The results of in vitro assays showed that TroIGFBP3 could stimulate macrophage activation and promote peripheral blood leukocytes (PBLs) proliferation. Meanwhile, TroIGFBP3 overexpression significantly inhibited bacterial infection in fish tissues, whereas TroIGFBP3 knockdown resulted in increased bacterial dissemination and colonization in golden pompano tissues in vivo. Furthermore, recombinant TroIGFBP3 could inhibit cellular proliferation and promote apoptosis of mouse tumor cells. Taken together, these results indicated that TroIGFBP3 plays a significant role in innate antibacterial immunity and provides a theoretical foundation for investigating the function of IGFBP3 in fish immune response.

Ustiloxin is a kind of 13-membered cyclic peptides found in mature rice false smut generated by Ustilaginoidea virens infecting rice spikelet. So far, six kinds of ustiloxins have been identified from false smut balls (FSBs) in which ustiloxin A is the main component. The toxins can not only inhibit the growth of rice, wheat, and corn, but also poison people and animals. However, so far, there have been few studies of the content of ustiloxin except that in mature FSB. The effect of ustiloxins on the process of infection has not been clarified. In this study, the technique of artificial inoculation coupled with UPLC-ESI–MS was introduced to investigate the content of ustiloxins in the course of infection. The initial formation time of ustiloxin A, B, C, D, F, and G was no later than 5, 5, 9, 7, 7, and 9 days post inoculation (dpi) prior to FSB’s formation, respectively. The content of ustiloxin A per spikelet was increased rapidly from 6.0 ng at 5 dpi to 14,157.1 ng at 25 dpi. Meanwhile, the content of ustiloxin A per dry weight (DW) of the FSBs also peaked at 1321.2 μg/g at 25 dpi. Interestingly, both the contents of ustiloxin A per dry weight and per spikelet were significantly reduced from 25 to 30 dpi. Transcriptome sequencing revealed that a total of 146 transcripts (103 upregulated and 43 downregulated) were significantly changed in rice spikelets after 3-h acute exposure to 100 ng ustiloxin A. In addition, several of the significantly altered genes were validated by RT-qPCR.

A previous study reported that exposure to tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) could promote the progression of hepatocellular carcinoma (HCC) in female HCC model zebrafish. Due to the existence of gender disparity in the development of HCC between females and males, whether the promotion effect of TDCIPP still exists in male HCC model zebrafish remains unclear. In this study, Tg(fabp10:rtTA2s-M2; TRE2:EGFP-krasG12V), referred as kras transgenic zebrafish which was shown to be an inducible liver tumor model, was applied as experimental model to assess the promotion potential of TDCIPP for HCC in males. In brief, kras males were exposed to 20 mg/L doxycycline (DOX), 0.3 mg/L TDCIPP and a binary mixture of 20 mg/L DOX with 0.3 mg/L TDCIPP, and after exposure liver size, histopathology and transcriptional profiles of liver from these treatments were examined. With the involvement of TDCIPP, the liver size was significantly increased and the lesion of hepatocyte became more aggressive. Furthermore, expressions of genes involved in DNA replication and inflammatory response were simultaneously up-regulated in the treatment of TDCIPP compared with the solvent control and in the treatment of the binary mixture of the two chemicals compared to the single DOX treatment. Overall, our results suggested that TDCIPP had promotion effect on the progression of liver tumor in kras males.

Nonvolatile taste active compounds, including free amino acids (FAAs), 5′-nucleotides, betaine, soluble sugars, trimethylamine oxide and organic acids of wild and cultured mud crab Scylla paramamosain were examined. The main taste in mud crab (MC) is derived from the FAAs, 5′-nucleotides, betaine, and organic acids, based on the fact that these compounds have a taste activity value (TAV) > 1. Wild MCs had a higher content of total FAAs, 5′-nucleotides, betaine, and organic acids in meat compared with cultured animals. However, no differences in the taste active compound levels were observed in the gonads of wild and cultured MCs, with betaine being the exception (wild crab > cultured crab). The total concentrations of FAAs in MC ranged from 12.71 to 36.94 mg/g. Monosodium glutamate (MSG)-like FAAs were primarily contributed by glutamic acid, and ranged from 0.71 to 0.93 mg/g. The concentrations of 5′-nucleotides were 1.10–2.24 mg/g, in which 5′-inosine monophosphate (IMP) and 5′-adenosine monophosphate (AMP) were the predominant TAVs (TAV > 1). The total concentrations of organic acids in MC were 2.41–11.10 mg/g, in which lactic and succinic acid in meat, and citric acid and succinic acid in female gonads were the main organic acids. The gonads were observed to have higher concentrations of 5′-nucleotides and organic acids compared with crab meat, with the equivalent umami concentration in gonads being higher than that in crab meat. In conclusion, wild MCs contained more active-taste nonvolatile flavor components relative to those detected in cultured MCs.

Previous studies reported that exposure to environmentally relevant concentrations of TDCIPP significantly decreased the number of cumulative eggs in zebrafish, but effects on the quantity of eggs and sperms remained unknown. Therefore, in this study, effects of TDCIPP on yolk diameter, surface morphology of eggs, sperm density and total motility were evaluated. First generation (F0) zebrafish larvae (Danio rerio) were exposed to 0, 50, 500 or 5000 ng/L tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) from 14 days post fertilization (dpf) to 120 dpf. The F0 generation of zebrafish were paired and F1 generation of embryos were collected and continuously exposed to the same concentrations of TDCIPP until 150 dpf. TDCIPP bioconcentration in the whole body as well as effects on survival and fecundity were evaluated in F1 generation. Exposure to TDCIPP resulted in an accumulation of the chemical and decreased survival of F1 generation of zebrafish. TDCIPP decreased cumulative production and changed surface morphology of eggs in females. In males, TDCIPP decreased total motility of sperm but did not affect sperm density. These effects on quality of egg and sperm might be responsible for the decreased hatching rates observed in cross mating experiments. Furthermore, TDCIPP exposure resulted in down-regulated gene expression related to gonadal development and maturation of germ cells in females or/and males, and the down-regulation was correlated to decreased fecundity. Taken together, the results suggested that exposure to TDCIPP could decrease the quantity of eggs and sperms by down-regulating the expression of genes related to gonadal development and maturation of germ cells in zebrafish.

Glycyrrhiza uralensis is a well-known herbal medicine that contains triterpenoid saponins as the predominant bioactive components, and these compounds include glycyrrhetinic acid (GA)-glycoside derivatives. Although two genes encoding UDP-glycosyltransferases (UGTs) that glycosylate these derivates have been functionally characterized in G. uralensis , the mechanisms of glycosylation by other UGTs remain unknown. Based on the available transcriptome data, we isolated a UGT with expression in the roots of G. uralensis . This UGT gene possibly encodes a glucosyltransferase that glycosylates GA derivatives at the 3-OH site. Biochemical analyses revealed that the recombinant UGT enzyme could transfer a glucosyl moiety to the free 3-OH or 30-COOH groups of GA. Furthermore, engineered yeast harbouring genes involved in the biosynthetic pathway for GA-glycoside derivates produced GA-3- O -β-D-glucoside, implying that the enzyme has GA 3-O-glucosyltransferase activity in vivo . Our results could provide a frame for understand the function of the UGT gene family, and also is important for further studies of triterpenoids biosynthesis in G. uralensis .

Tris (2-butoxyethyl) phosphate (TBOEP) is an environmental contaminant that poses serious risks to aquatic organisms and their associated ecosystem. Recently, the reproductive and developmental toxicology of TBOEP has been reported. However, fewer studies have assessed the neurotoxic effects in zebrafish (Danio rerio) larvae. In this study, zebrafish embryos were subjected to waterborne exposure of TBOEP at 0, 50, 500, 1500 and 2500 μg/L from 2 to 144-h post-fertilization (hpf). Behavioral measurements showed that TBOEP exposure reduced embryonic spontaneous movement and decreased swimming speed of larvae in response to dark stimulation. In accordance with these motor effects, TBOEP treatment reduced neuron-specific GFP expression in transgenic Tg (HuC-GFP) zebrafish larvae and inhibited the growth of secondary motoneurons, as well as decreased expression of marker genes related to central nervous system development in TBOEP treated group. Furthermore, increased concentrations of reactive oxygen species (ROS) and malondialdehyde (MDA), as well as reduction of SOD activity were detected in TBOEP exposure group. The present results showed that the alteration in motor neuron and oxidative stress could together lead to the motor behavior alterations induced by TBOEP.

It is hypothesized that polychlorinated diphenyl sulfides (PCDPSs) induce lethal toxicity in zebrafish which is mediated by aryl hydrocarbon receptor 2 (Ahr2) activation. In this study an assay was developed based on in vivo exposure of wild-type and Tg(cyp1a:gfp) transgenic zebrafish embryos/larvae to PCDPS congeners (i.e., six dichloro- to heptachloro-diphenyl sulfides) coupled with a zebrafish Ahr2-luciferase reporter gene (LRG) expression. Waterborne PCDPSs were found to be accumulated in zebrafish larvae, and exposure to PCDPSs led to a significant increase in mortality and cyp1s mRNA expression. Furthermore, treatment with PCDPSs caused a significant induction of Ahr2-LRG activity in COS-7 cells, and extremely significant correlations were observed between the in vivo median lethal concentrations and the levels of cyp1s mRNA expression and Ahr2 activation. Molecular dynamics simulations indicated the interaction between dioxins/dioxin-like compounds (DLCs) and six key amino acid residues in the ligand-binding domain of Ahr2 probably determined the susceptibility to dioxins/DLCs in zebrafish. These results strongly support the hypothesis that early life-stage mortality of zebrafish is initiated and mediated by Ahr2 activation.

The additive flame retardant triphenyl phosphate (TPHP) has been frequently detected in environments and biota. Evidences indicate that TPHP has potential risks to aquatic organisms. Seldom has been reported about its chronic effects to aquatic organism at low trophic levels, such as Cladocera. In the present study,12 h old Daphnia magna (D. magna) were exposed to 0, 5, 50 or 500 μg/L TPHP for 21 days to investigate the chronic effects of TPHP on body length, fecundity and survival. Meanwhile, D. magna PCR arrays were used to evaluate the transcriptional responses of 155 genes involved in 40 pathways. Exposure to 500 μg/L TPHP for 21 days significantly decreased the body lengths of both F0 and F1 generation and inhibited the fecundity of F0 generation. Results of RT-qPCR showed that the expressions of 76 genes involved in 15 pathways were significantly altered after exposure to 500 μg/L TPHP for 21 days. The significantly altered pathways related to genetic information processing, cellular process and metabolism might be responsible for the observed effects of TPHP. Overall, our results showed that chronic exposure to TPHP caused developmental and reproductive toxicities to D. magna.

This work focuses on the transgenerational effects of titanium dioxide nanoparticles (n-TiO2) and microcystin-LR (MCLR) on the development of F1 zebrafish offspring. Wild-type adult zebrafish (4 months old) were exposed to various MCLR concentrations (0, 0.5, 4, and 32 μg L−1) with and without n-TiO2 (100 μg L−1) for 45 days. F1 zebrafish embryos from the above-mentioned parents were collected and cultured in clean water for 120 hours post-fertilization (hpf). Our results showed that n-TiO2 could potentially be transferred from parents to offspring, which further led to the increase in the accumulation of MCLR content in F1 zebrafish embryos. Hypoactivity and indistinct retinal layers in F1 larvae were observed, and the presence of n-TiO2 intensified these adverse effects in co-exposure groups. The parental transfer of MCLR and n-TiO2 further increased the formation of reactive oxygen species (ROS) in F1 larvae, which contributed to more apoptotic cells in and around the eyes of F1 larvae. Furthermore, we detected altered gene expression (p53, Bax, Bid, Bcl-2, puma, and Apaf-1), protein expression (P53, Bax, Bcl-2, and cytochrome c) and enzyme activities (caspase-3, caspase-8, and caspase-9), indicating that parental transfer of n-TiO2 could aggravate MCLR-induced apoptosis in F1 offspring through the mitochondria-mediated apoptosis pathway. In summary, this research studied the bioaccumulation, parental transfer, and developmental toxicity of MCLR and n-TiO2 to examine their interactions, revealing that the health risks of co-exposure should not be ignored.

The aim of the present study was to investigate the reproductive effects of microcystin-LR (MCLR) in the presence of titanium dioxide nanoparticles (n-TiO2). Five-month-old zebrafish were exposed to MCLR (0, 0.5, 4 and 32 μg L−1) alone or combined with n-TiO2 (100 μg L−1) for 21 days. The accumulation of both n-TiO2 and MCLR was observed in the fish liver, brain and gonad. Enhanced bioconcentration of MCLR was measured in coexposure groups. Joint exposure to both n-TiO2 and MCLR significantly reduced the fecundity of adult fish compared to the MCLR-only treatment. Histopathological examination revealed no obvious change in the morphology of the ovary and testis, while a significant decline of estradiol (E2) and testosterone (T) levels as well as disordered transcription patterns of genes along the hypothalamus–pituitary–gonadal (HPG) axis was observed. N-TiO2 may act as a carrier of MCLR and increase its concentration upon coming in contact with zebrafish, which exacerbated the reproductive endocrine dysfunction as a consequence.

Microcystin-LR (MC-LR) is widely distributed in the natural environment and causes hepatotoxicity. However, whether MC-LR promotes liver tumor progression remains controversial. krasV12 transgenic zebrafish were used as an inducible liver tumor model to evaluate the potential tumor-promoting effect of MC-LR. First, krasV12 transgenic larvae were exposed to 0, 0.1 and 1 mg/L MC-LR with 20 mg/L doxycycline (Dox) for 4 d. The gray values and histopathological examinations of the liver demonstrated that MC-LR aggravated liver tumor progression, which could be inhibited by the Protein arginine methyltransferase 5 (Prmt5) inhibitor compound 5 (CMP5). Second, 1-month-old juvenile transgenic zebrafish were exposed to 0, 20 mg/L Dox, 1 μg/L MC-LR, and 20 mg/L Dox with 0.1 or 1 μg/L MC-LR for 15 d to determine whether the exposure to environmental concentrations of MC-LR promoted hepatocellular carcinoma (HCC) progression. We found that environmental concentrations of MC-LR increased the hepatosomatic index (HSI) and gray value (intensity/area) and promoted HCC progression. The results indicate that environmental concentrations of MC-LR have the potential to promote liver tumor progression. Taken together, the present study demonstrates that MC-LR can promote tumor in krasV12 transgenic zebrafish and that the upregulation of prmt5 expression might contribute to MC-LR-mediated promotion of liver tumorigenesis.

Cathepsin B (CTSB) is one of the typical representatives of cysteine protease family. It has the activity of both exopeptidase and endopeptidase. It plays an important role in antigen presentation, degradation, apoptosis, inflammatory response and physiological process of many diseases. In this study, CTSB of Trachinotus ovatus (TroCTSB) was cloned, and its structure and function were analyzed. The results showed that the coding region of TroCTSB was 993 bp, encoding 330 amino acid residues. The homology analysis showed that the amino acid sequence of TroCTSB was similar to that in other teleosts and mammals (68.69%–88.48%). Under normal physiological conditions, TroCTSB was widely distributed in various tissues with the highest expression level in stomach, followed by liver, and the lowest expression level in blood. The optimal pH and temperature of purified recombinant protein rTroCTSB were 5.5 and 40 °C, respectively. The toxicity test of metal ions showed that Fe2+, Cu2+, Ca2+ and Zn2+ could all inhibit the activity of TroCTSB, with Zn2+ ranking the first. In addition, after Edwardsiella tarda infection, the expression of TroCTSB was significantly up-regulated in liver, spleen and head kidney. The overexpression of TroCTSB significantly inhibited the infection of E. tarda in golden pompano tissues, and the knockdown of TroCTSB remarkably promoted the reproduction of E. tarda in golden pompano tissues in vivo. This study suggests that TroCTSB was involved in the antibacterial immune response of T. ovatus, and provided a reference for further research in elucidating the resistance mechanism of TroCTSB.