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Trehalase plays an important role in insect metabolism and development by hydrolyzing blood sugar trehalose, but it seems to perform primarily an immunomodulatory function in crustaceans whose blood sugar is glucose. Metal ions as pollutants seriously affecting crustacean health, but studies on trehalase in metal immunity are still limited. In this study, a soluble trehalase (NdTre1) that could bind to multiple metals was identified from Neocaridina denticulata sinensis for investigating metal resistance. Expression profiling revealed that NdTre1 was mainly expressed in the gill and was significantly decreased following stimulation with copper (Cu²⁺) and cadmium (Cd²⁺). Transcriptomic analysis of gills revealed an increase in ecdysone synthesis after interference with NdTre1. Increased ecdysone activated the endogenous mitochondrial pathway and the mitogen activated protein kinase (MAPK) pathway to further induced apoptosis. In vitro , Escherichia coli overexpressing recombinant NdTre1 had higher survival and faster growth rates to better adapted the metal-containing medium. Overall, NdTre1 exercises an important immune function in shrimp resistance to metal stimulation by regulating apoptosis and molting. Further investigation can further explore specific response mechanisms of NdTre1 to multiple metals. [Display omitted] • NdTre1 resists metal stress by regulating cell apoptosis and MAPK pathways. • Specific response mechanisms of NdTre1 after metal stimulation vary. • Tre1 in crustaceans primarily regulates immunity rather than development. [ABSTRACT FROM AUTHOR]

During the immune defense reaction of invertebrate, a plenty of reactive oxygen species (ROS) could be induced to product. Though ROS can kill foreign invaders, the accumulation of these reactive molecules in animals will cause serious cell damage. Carotenoids could function as scavengers of oxygen radicals. In this research, cDNA and genomic DNA of one carotenoid isomerooxygenase gene (named EcNinaB-X1) were cloned from Exopalaemon carinicauda. EcNinaB-X1 gene was composed of 12 exons and 11 introns. EcNinaB-X1 knock-out (KO) prawns were produced via CRISPR/Cas9 technology and the change of their phenotypes were analyzed. Of the 400 injected one-cell stage embryos with cas9 mRNA and one sgRNA targeting the first exon of EcNinaB-X1 gene, 26 EcNinaB-X1- KO prawns were generated and the mutant rate reached 6.5% after embryo injection. The EcNinaB-X1- KO prawns had significant lower mortality than those in wild-type group when the prawns were challenged with Vibrio parahaemolyticus or Aeromonas hydrophila. In conclusion, we first demonstrate the function of the carotenoid isomerooxygenase gene in immune defense of E. carinicauda by performing directed, heritable gene mutagenesis. Image 1 • EcNinaB-X1 gene was cloned from E. carinicauda. • The expression profiles of EcNinaB-X1 were demonstrated. • CRISPR-Cas9 system efficiently generated indels in EcNinaB-X1 loci. • EcNinaB-X1 -KO prawns had lower mortality than wild-type after bacterial challenge. [ABSTRACT FROM AUTHOR]

This study investigates the impact of China's Low-Carbon Pilot Policy on analyst forecast behaviors. Using a staggered difference-in-difference approach, we find that the program reduced analyst forecast errors and divergence, as mandatory sustainability disclosures enable analysts to incorporate new information to improve forecast quality. The effect is concentrated in state-owned firms and manufacturing-oriented cities. Additional tests explore accounting information quality and investor attention as plausible channels. Overall, exploiting a major Chinese environmental regulation, we provide novel evidence that green policies can enhance transparency and capital market efficiency. The findings offer implications for regulators, investors, and managers as countries pursue climate change mitigation strategies. • Low-Carbon Pilot Policy reduced analyst forecast errors and divergence. • Forecast improvements concentrated in state-owned firms & manufacturing-oriented cities. • Accounting information quality and investor attention are plausible channels. [ABSTRACT FROM AUTHOR]

Chitin deacetylase (CDA, EC 3.5.1.41), belonging to a family of extracellular chitin-modifying enzymes, can catalyze the deacetylation of chitin. In this study, the full-length cDNA sequence encoding chitin deacetylase 1 ( EcCDA1 ) was obtained from Exopalaemon carinicauda . The complete nucleotide sequence of EcCDA1 contained a 1611 bp open reading frame (ORF) encoding EcCDA1 precursor of 536 amino acids. The domain architecture of the deduced EcCDA1 protein contained a signal peptide, a chitin-binding peritrophin-A domain (ChtBD2), a low-density lipoprotein receptor class A domain (LDLa) and a Polysacc_deac_1 domain. EcCDA1 mRNA was predominantly expressed in the gills. The expression of EcCDA1 in the prawns challenged with Vibrio parahaemolyticus and Aeromonas hydrophila changed in a time-dependent manner. The expression of EcCDA1 in the prawns challenged with V. parahaemolyticus was up-regulated at 12 h ( p  < 0.05), and significantly up-regulated at 24 h and 48 h ( p  < 0.01), and then returned to the control levels at 96 h post-challenge ( p  > 0.05). At the same time, the expression in Aeromonas -challenged group was significantly up-regulated at 12, 24 and 48 h ( p  < 0.01) and returned to the control levels at 120 h post-challenge ( p  > 0.05). Then, EcCDA1 was recombinantly expressed in Pichia pastoris and the purified recombinant EcCDA1 could not inhibit the growth of V. parahaemolyticus or A. hydrophila , which indicated that the CDA1 may play its biological activity in immune defense by deacetylation from chitin. [ABSTRACT FROM AUTHOR]

Chitinase, belonging to family 18 glycosyl hydrolase, is a multi-gene family and it has many functions. Generation of loss-of-function mutant targeting an interesting gene is a common way to clarify its function based on reverse genetics. In this study, we first reported the immune defense of a chitinase gene ( EcChi4 ) in Exopalaemon carinicauda using its EcChi4 -deletion mutant. EcChi4 was predominantly expressed in hepatopancreas and was upregulated after challenge with Vibrio parahaemolyticus or Aeromonas hydrophila . After knockout EcChi4 gene using CRISPR/Cas9 tool, the prawns in EcChi4 -deletion group had significant higher mortality than those in wild-type group when the prawns were challenged with V. parahaemolyticus or A. hydrophila . In conclusion, we first demonstrate the function of a chitinase gene in immune defense of E. carinicauda by performing directed, heritable gene mutagenesis. In the future, CRISPR/Cas9 should be widely applicable as a feasible means for gene editing in E. carinicauda for the study of important biological questions that cannot be easily addressed in other decapods. [ABSTRACT FROM AUTHOR]

Edwardsiella tarda has been recognized as an important facultative intracellular pathogen of fish with capability of survival and replication within macrophages. E. tarda -macrophage interactions play a very important role in the defense mechanism of fish against infection. The mechanisms that E. tarda use to infect and persist inside macrophages are not well characterized. To gain insight concerning this process, RAW264.7 cells was used to investigate the interactions between E. tarda and macrophages. Using an in vitro model involving RAW264.7 cells, internalization assay demonstrated that MOIs of 10:1 and 100:1 could result in a satisfactory infection rate after a 2 h infection period. Consistent with the performance in fish macrophages, E. tarda could survive, replicate and induce iNOS-mediated NO production in RAW264.7 cells. Light and electron microscopy confirmed the internalization and replication of E. tarda in RAW264.7 cells, showing once inside macrophages, numberous bacteria may be destroyed within phagolysosomes and those that successfully subvert phagocyte defenses are capable of extensively replicating within the vacuolar-like compartment in macrophages. In addition, E. tarda -induced apoptosis was observed in RAW264.7 cells in a dose-and time-dependent manner, characterized by increased Annexin V binding and the activation of caspase-3. The results described here indicate that RAW264.7 cells could model the behavior of fish macrophages in response to E. tarda in many ways and may serve as a cell model for study on interactions between E. tarda and macrophages. The successful establishment of E. tarda- invaded RAW264.7 cells model may contribute to providing a basis for more detailed understanding of E. tarda pathogenesis. [ABSTRACT FROM AUTHOR]

To evaluate the role of Toll-like receptor 2 (TLR2) signaling in retinal neovascularization in a mouse model of oxygen-induced retinopathy (OIR). The OIR model was established in C57BL/6J wild type (WT) mice and TLR2−/− mice. Retinal neovascularization in the OIR model was measured by counting new vascular cell nuclei above the internal limiting membrane and analyzing flat-mounted retinas perfused with fluorescein dextran and immunostained with Griffonia Simplicifolia (GS) isolectin. The expression of TLR2 and VEGF in the retina was detected by immunofluorescence. Expression of TGF- β1, b-FGF, and IL-6 mRNA in the retina was measured by quantitative real-time PCR. Compared to WT OIR mice, retinal neovascularization was attenuated in TLR2−/− OIR mice. The co-expressions of TLR2 and VEGF were remarkably and consistently increased in WT OIR mice; however, there was no expression of TLR2 and a significant decrease in VEGF expression in TLR2−/− OIR mice. These results suggest that TLR2 plays a central role in OIR model angiogenesis. Expression of TGF- β1, b-FGF, and IL-6 mRNA were reduced in the TLR2−/− OIR mice, suggesting that the inflammatory response induced by TLR2 relates to angiogenesis. TLR2 signaling in the retina is associated with neovascularization in mice. Inflammation contributes to the activation of angiogenesis and is partially mediated through the TLR2-VEGF retinal signaling pathway. [ABSTRACT FROM AUTHOR]

The recently emerged CRISPR/Cas9 technology is the most flexible means to produce targeted mutations at the genomic loci in a variety of organisms. In Crustaceans, molt-inhibiting hormone (MIH) is an important negative-regulatory factor and plays a key role in suppressing the molting process. However, whether precise disruption of MIH in crustacean can be achieved and successfully used to improve the development and growth has not been proved. In this research, the complementary DNA (cDNA) and genomic DNA, including flanking regions of the MIH gene ( EcMIH ) of ridgetail white prawn Exopalaemon carinicauda, were cloned and sequenced. Sequence analysis revealed that EcMIH was composed of three exons and two introns. Analysis by RT-PCR showed that EcMIH mainly expressed in eyestalks. During different development periods, EcMIH was highest in juvenile stage and extremely low in others but adult prawns eyestalks. In addition, we applied CRISPR/Cas9 technology to generate EcMIH knock-out (KO) prawns and then analyzed the changes in their phenotypes. We efficiently generated 12 EcMIH-KO prawns out of 250 injected one-cell stage embryos and the mutant rate reached 4.8% after embryo injection with one sgRNA targeting the second exon of EcMIH . The EcMIH -KO prawns exhibited increased the body length and shortened the metamorphosis time of larvae from mysis larva to postlarva. Meanwhile, EcMIH -KO did not cause the health problems such as early stage death or deformity. In conclusion, we successfully obtained EcMIH gene and generated EcMIH -KO prawns using CRISPR/Cas9 technology. This study will certainly lead to a wide application prospect of MIH gene in prawns breeding. [ABSTRACT FROM AUTHOR]

Edwardsiella tarda is an important facultative intracellular pathogen infecting a wide range of host from fish to humans. This bacterium could survive and replicate in macrophages as an escape mechanism from the host defense. E. tarda -macrophage interaction is vital in determining the outcome of edwardsiellasis. To fully elucidate the pathogenesis of E. tarda , the differential proteomes of RAW264.7 cells in response to E. tarda -infection, were analyzed at different time points with two-dimensional gel electrophoresis (2-DE) followed by liquid-chromatography-tandem mass spectrometry (LC-MS/MS) identification. 26 altered proteins (18 up-regulated and 8 down-regulated proteins) were successfully identified, which are mainly involved in formation of phagosomes, macrophage microbicidal activity and anti-apoptosis of macrophage. Moreover, 6 corresponding genes of the differentially expressed proteins were quantified by quantitative real-time PCR (qPCR) to examine the transcriptional profiles. Western blot analysis further confirmed the differential expression of 5 proteins in the proteomic profiles. Based on these findings, we hypothesize that these differentially expressed proteins likely play a pivotal role in determining the course of E. tarda -infection. The result suggested that E. tarda could develop some strategies to achieve a successful intracellular lifestyle, including modulation of phagosome biogenesis, resistance to macrophage microbicidal agent and anti-apoptosis of macrophages. Thus, this work effectively provides useful and novel protein-related information to further understand the underlying pathogenesis of E. tarda -infection. [ABSTRACT FROM AUTHOR]

Hematopoietic stem progenitor cells (HSPCs) give rise to the hematopoietic system, maintain hematopoiesis throughout the lifespan, and undergo molecular and functional changes during their development and aging. The importance of hematopoietic stem cell (HSC) biology has led to their extensive characterization at genomic and transcriptomic levels. However, the proteomics of HSPCs throughout the murine lifetime still needs to be fully completed. Here, using mass spectrometry (MS)-based quantitative proteomics, we report on the dynamic changes in the proteome of HSPCs from four developmental stages in the fetal liver (FL) and the bone marrow (BM), including E14.5, young (2 months), middle-aged (8 months), and aging (18 months) stages. Proteomics unveils highly dynamic protein kinetics during the development and aging of HSPCs. Our data identify stage-specific developmental features of HSPCs, which can be linked to their functional maturation and senescence. Our proteomic data demonstrated that FL HSPCs depend on aerobic respiration to meet their proliferation and oxygen supply demand, while adult HSPCs prefer glycolysis to preserve the HSC pool. By functional assays, we validated the decreased mitochondrial metabolism, glucose uptake, reactive oxygen species (ROS) production, protein synthesis rate, and increased glutathione S-transferase (GST) activity during HSPC development from fetal to adult. Distinct metabolism pathways and immune-related pathways enriched in different HSPC developmental stages were revealed at the protein level. Our study will have broader implications for understanding the mechanism of stem cell maintenance and fate determination and reversing the HSC aging process. • FL HSPCs depend on aerobic respiration to meet the proliferation, while adult HSPCs prefer glycolysis to preserve HSC pool. • Higher levels of GSH in adult HSPCs protect them from oxidative stress. • We validated the decreased mitochondrial metabolism, glucose uptake, ROS levels, protein synthesisduring HSPC development. • Immune-related pathways are enriched in adult HSPCs, while metabolic-related pathways are enriched in FL HSPCs. [ABSTRACT FROM AUTHOR]

Triacylglycerol lipases (TGLs) can catalyze the hydrolysis reaction of triacylglycerol serving multiple functions in most organisms. Based on the genomic and transcriptomic databases of Neocaridina denticulata sinensis , two TGL genes from N. denticulata sinensis designated NdTGL1 and NdTGL2 were identified and characterized. NdTGL1 showed the highest expression in the stomach, followed by the testis and hepatopancreas, and NdTGL2 exhibited the maximum expression in the hepatopancreas, followed by the stomach and heart. Under the stimulation of copper ion, the expression of NdTGL1 peaked at 12 h and the expression of NdTGL2 elevated significantly at 24 h after stimulation (P < 0.05). It is speculated that NdTGLs may play an important role in the stress response of N. denticulata sinensis. Challenged with Vibrio parahaemolyticus , the expression profiles of NdTGL1 and NdTGL2 in the hepatopancreas was different, which indicates that the immune response of the V. parahaemolyticus challenge might lead to changes in triglyceride metabolism. The recombinant NdTGL (recNdTGL1 and recNdTGL2) were obtained and the enzymatic characterization of recNdTGL1 and recNdTGL2 were determined. The common maximum activity and stability of the recNdTGL1 and recNdTGL2 were observed at 45 °C and 10 °C, respectively. Both recNdTGL1 and recNdTGL2 exhibited the highest activity at pH 10.0. Furthermore, the recNdTGL1 and recNdTGL2 displayed the maximum stability at pH 5.0 and pH 8.0, respectively. In presence of different metal ions, the enzyme activity of recNdTGL1 and recNdTGL2 were inhibited by Cu2+ and Zn2+, and decreased by about 25%. Studies on the triacylglycerol lipases of N. denticulata sinensis provide theoretical support for studies related to fat metabolism in crustaceans and studies on response mechanism of digestive enzymes to microbial pathogens. [Display omitted] • Two TGL genes of N. denticulata sinensis were firstly identified and charactered. • NdTGL1 was highly expressed in stomach and NdTGL2 had the maximum expression in hepatopancreas. • The expression levels of NdTGLs were elevated after the stimulation of Cu2+ and changed under the V. parahaemolyticus challenge. • The recNdTGLs exhibited high activity in alkaline pH and displayed high stability at low temperature. [ABSTRACT FROM AUTHOR]

Vibrio parahaemolyticus causes serious economic losses to the shrimp farming industry. There is still a lack of adequate understanding of the changes in the overall response of N. denticulata sinensis caused by V. parahaemolyticus , particularly with respect to gill tissue, which is severely damaged by the pathogen. In this study, a total of 1358 differentially expressed genes were identified between the PBS control and Vibrio stimulation groups using transcriptome sequencing techniques. After further screening and analysis, many immune-related genes were obtained, involving lysosome pathway, metabolic process, chitin-binding protein, and serine protease family members. In addition, we randomly selected six DEGs in the lysosome pathway for qRT-PCR verification, and the results showed that their expression patterns were consistent with the RNA-seq. The results demonstrate the molecular regulation of the gill tissue response to V. parahaemolyticus infection in N. denticulata sinensis , contributing to the understand of the complex and efficient innate immune system and defense mechanisms in crustaceans. [Display omitted] • Immune response of N. denticulata sinensis gill to V. parahaemolyticus infection was clarified using RNA-seq. • Lysosome pathway, metabolic process, chitin-binding protein, and serine protease were found to participate immune response. • qRT-PCR results of randomly selected 6 immune-related genes were consistent with those of RNA-seq. [ABSTRACT FROM AUTHOR]

Neocaridina denticulata sinensis possesses characters of rapid growth, tenacious vitality, short growth cycle, transparent, and easy feeding. Therefore, it is gradually being developed into an animal model for basic research on decapod crustaceans. Herein, a Cu/Zn superoxide dismutase (Cu/Zn-SOD), named as Nd-ecCu/Zn-SOD, was identified and characterized from N. denticulata sinensis. The full-length cDNA sequence of Nd-ecCu/Zn-SOD is 829 bp containing a 684 bp open reading frame, which encodes a protein of 227 amino acid residues with a typical Sod_Cu domain. The quantitative real-time PCR analysis showed that Nd-ecCu/Zn-SOD mRNA was expressed in all the tested tissues. Under challenge with copper, the mRNA expression of Nd-ecCu/Zn-SOD reached the maximum at 6 h, and decreased until 24 h. After 24 h of exposure, its expression was up-regulated significantly at 36 h. After then its expression sharply decreased with a comeback at 48 h. The result indicated that Nd-ecCu/Zn-SOD might play an important role in the stress response of N. denticulata sinensis. The expression of Nd-ecCu/Zn-SOD in gills challenged with Vibrio parahaemolyticus changed in a time-dependent manner. Nd-ecCu/Zn-SOD was lowly expressed in early developmental stages by RNA-Seq technology, yet it showed that a cyclical rise and fall occurred between middle stages and late stages. In addition, Nd-ecCu/Zn-SOD was recombinantly expressed using E. coli and the recombinant protein was purified as a single band on SDS-PAGE. The recombinant Nd-ecCu/Zn-SOD (rNd-ecCu/Zn-SOD) existed enzymatic activity under a wide range of temperature and pH. The exposure of metal ions was found that Zn2+, Mg2+, Ca2+, Ba2+, and Cu2+ could inhibit the enzymatic activity of rNd-ecCu/Zn-SOD, and Mn2+ increased the enzymatic activity of rNd-ecCu/Zn-SOD. These results indicate that Nd-ecCu/Zn-SOD may play a pivotal role in resistant against oxidative damage and act as a biomarker under stressful environment. [Display omitted] • It is the first time to clarify extracellular Cu/Zn-SOD in N. denticulata sinensis. • The mRNA expression profile was clarified after challenges. • The mRNA expression was performed during different developmental stages of embryos. • The rNd-ecCu/Zn-SOD enzymatic characterization was characterized. [ABSTRACT FROM AUTHOR]

Peroxiredoxin (Prx) is an antioxidant protein that widely exists in various organisms. To further investigate the role of Prx in the antioxidant and immune responses of Neocaridina denticulata sinensis , the full-length cDNA sequence of a Prx gene (Nd-Prx) from N. denticulata sinensis was obtained. The open reading frame (ORF) of Nd-Prx is 597 bp and encodes 198 amino acids. Amino acid similarity alignment showed that Nd-Prx contained a conserved sequence region "FYPLDFTFVCPTEI". qRT-PCR assay showed that Nd-Prx was expressed in all tested tissues and its expression was highest in the ovary. Nd-Prx was most highly expressed at 36 h after copper stimulation. Nd-Prx expression levels in hepatopancreas were significantly upregulated after Vibrio parahaemolyticus challenge (P < 0.05). In addition, the recombinant Nd-Prx was prepared and its enzyme activity was most stable at 70 °C with pH of 6.0. The antioxidant activity and DNA protection of recombinant Nd-Prx was also demonstrated. In summary, this study investigated the role of Prx in antioxidant and immune responses of N. denticulata sinensis , which might provide a foundation for further exploring Prx in immune system of crustaceans and for the application in disease control. [Display omitted] • Nd-Prx gene was cloned and its recombinant protein was prepared to analyze its enzymatic activity. • Nd-Prx was expressed in all tested tissues. • Expression of Nd-Prx was elevated under copper exposure or V. parahaemolyticus challenge. • The recombinant Nd-Prx exhibited high reducibility. [ABSTRACT FROM AUTHOR]

Crustins are a kind of antibacterial peptides (AMP) existing in crustaceans, and their antibacterial abilities are considered to be related to the conserved WAP domain. In this study, a novel type I Crustin gene was identified in Exopalaemon carinicauda , named EcCru. The deduced amino acid sequence revealed that the conserved cysteine at position 7 in the WAP domain was replaced by aspartic acid. The gene is 405 bp in length, encoding 134 amino acids, and is mainly distributed in gills and hepatopancreas. After Vibrio parahaemolyticus and Aeromonas hydrophila stimulation, the expression of EcCru was significantly up-regulated within 12 h, and then returned to normal levels. The recombinant protein was obtained using the Pichia pastoris expression system, and the recombinant protein had neither antibacterial activity against gram-positive or gram-negative bacteria. But the antibacterial ability emerged when Asp101 was mutated to Cys. Notably, we also obtained a mutant that had a deletion at the 6 th conserved Cys in the WAP domain, and this mutant had antibacterial ability against gram-positive bacteria Bacillus subtilis and B. cereus. This indicates that the conserved cysteine with different positions in WAP domain can have different effects on the antibacterial ability of Crustins. [Display omitted] • A novel type I crustin gene was obtained from Exopalaemon carinicauda (EcCru). • EcCru expression profiles were determined after prawns were challenged with pathogens. • Two mutations of conserved Cys in the WAP domain of EcCru lead to increase its antibacterial ability. [ABSTRACT FROM AUTHOR]

This study investigates an L-type lectin, NdLTL1 , derived from Neocaridina denticulata sinensis , emphasizing its role in immune defense through carbohydrate binding and bacterial agglutination. Bioinformatics analysis identified 179 lectin sequences, leading to subsequent investigations into the structure and function of NdLTL1. The open reading frame (ORF) of NdLTL1 spans 966 bp and encodes a protein consisting of 321 amino acids (36.25 kDa), which features a signal peptide, a transmembrane domain and Lectin_leg-like domain. Three-dimensional modeling revealed three antiparallel β-sheets characteristic of Lectin_leg-like domain, confirming evolutionary links with proteins such as VIP36. Protein-carbohydrate and protein-protein interaction studies showed that NdLTL1 binds to both carbohydrates like N-acetylglucosamine, peptidoglycan, lipopolysaccharides (LPS), and mannose, as well as sorting proteins (COPI/COPII). Gene expression analyses indicated that NdLTL1 exhibits the highest expression levels in cardiac tissues and significant upregulation in gills following exposure to Vibrio parahaemolyticus. Recombinant NdLTL1 expressed in Escherichia coli was shown to bind multiple bacterial strains and exhibit calcium-dependent agglutination properties. Enzyme-linked immunosorbent assay (ELISA) confirmed concentration-dependent carbohydrate binding, particularly rapid for LPS. In vitro experiments suggested that recombinant NdLTL1 may promote bacterial growth under nutrient-limited conditions while potentially triggering immune defenses indirectly. • Deep sequencing identified 179 sequences similar to lectins in Neocaridina denticulata sinensis. • NdLTL1, a 321-amino-acid protein, shares high similarity with the VIP36 subtype. • NdLTL1 binds to carbohydrates and shows calcium-dependent bacterial agglutination. • NdLTL1 expression increases in gill tissue during Vibrio parahaemolyticus infection. • NdLTL1 accelerates bacterial agglutination in vitro , playing a key role in immune response. [ABSTRACT FROM AUTHOR]

Peroxiredoxin (Prx) is an antioxidant protein family, which widely exists in organisms and plays an important role in innate immunity. In this study, the full-length cDNA of a Prx gene (NdPrx) was obtained from Neocaridina denticulata sinensis , which contains a 735 bp open reading frame (ORF) and encodes a polypeptide of 244 amino acids. It is inferred that the molecular weight of the encoded amino acid is 27261.20 Da and the theoretical isoelectric point is 6.16. Phylogenetic analysis shows that NdPrx and Prx4 have high homology, so it was named NdPrx4. Multiple alignment analysis showed that the amino acid sequence of NdPrx4 had high homology with Prx4 of other species, and the similarity with Homarus americanus was the highest, 92.86%. Quantitative real-time PCR analysis showed that NdPrx4 was expressed in various tissues of N. denticulata sinensis , and the expression in ovary was the highest. It was speculated that NdPrx4 may be related to maternal immune function. Under the stimulation of Cu2+, the expression of NdPrx4 reached the peak at 36 h, and showed a downward trend until 72 h, indicating that NdPrx4 may play an important role in the stress response of N. denticulata sinensis. Then, NdPrx4 was recombinantly expressed in E. coli , and its enzymatic characteristics of rNdPrx4 were detected. The result showed that the activity of rNdPrx4 was the highest at pH 5.0 and 55 °C. It was found that Mn2+ and Ca2+ can inhibit the activity of rNdPrx4, and Zn2+ increases the activity of rNdPrx4. • The full-length cDNA sequence of NdPrx4 was cloned and analyzed. • NdPrx4 was predominantly expressed in ovary of N. denticulata sinensis. • NdPrx4 was upregulated after copper ion stimulation. • NdPrx4 was recombinantly expressed and the enzymatic characterization was determined. [ABSTRACT FROM AUTHOR]

As a common aquatic pathogen, Vibrio parahaemolyticus can cause a variety of diseases of shrimp, especially acute hepatopancreatic necrosis disease (AHPND), which leads to great losses to the aquaculture industry around the world. However, the molecular mechanism of V. parahaemolyticus infection is still unclear. Neocaridina denticulate sinensis is a kind of small ornamental shrimp that is popular in aquarium trade, and due to its tenacious vitality, rapid growth, high reproductive capacity, it is very suitable to be developed as an animal model for basic research on decapod crustaceans. Thus, in this paper, transcriptomes of N. denticulate sinensis hepatopancreas with or without V. parahaemolyticus injection were explored. The results showed that a total of 23,624 genes with the N50 of 2705 bp were obtained. Comparative transcriptomic analysis revealed 21,464 differentially expressed genes between the V. parahaemolyticus infected and non-infected group, of which, 11,127 genes were up-regulated and 10,337 genes were down-regulated. Functional enrichment analysis suggested that many DEGs enriched in immune related pathways, including MAPK signaling pathway, Phosphatidylinositol signaling system, Chemokine signaling pathway, Phagosome and Jak-STAT signaling pathway and so on. Eight genes were selected randomly for qRT-PCR to verify the transcriptome sequencing results and the results showed the expression of these genes were consistent with the transcriptome results. Our work provides a unique and important dataset that contributes to the understanding of the molecular mechanisms of the immune response to V. parahaemolyticus infection and may further provide the basis for the prevention and resolution of bacterial diseases. • Transcriptomic analysis of hepatopancreas from Neocaridina denticulate sinensis challenged with Vibrio parahemolyticus. • A total of 21,464 DEGs were identified, including 11127 up-regulated genes and 10337 down-regulated genes. • Many DEGs were enriched in immune-related pathways, and expression of some PRRs and immune related factors were also altered. • Expression tendencies of 8 randomly selected genes were consistent with the result from transcriptomic analysis. [ABSTRACT FROM AUTHOR]

Neocaridina denticulate sinensis is a promising crustacean model species due to its merits in raising and breeding. However, its molecular responses to copper remains largely unknown. In the present research, RNA-seq was used to mine the alteration in transcriptome of N. denticulate sinensis hepatopancreas under copper exposure. A total of 16,423 DEGs was identified between control and Cu2+ treatment groups. GO enrichment analysis of all DEGs suggested down-regulated genes exceeded up-regulated genes in all the significantly enriched terms, except for RNA polymerase III complex (GO:0005666). KEGG analysis showed Cu exposure only induced two significantly enriched pathways, including Phagosome (ko04145) and Pathogenic Escherichia coli infection (ko05130). Besides, pattern recognition receptors as Toll , lectin B , CTL1 and SRB , AMPs as crustin type I , lysozyme , and NOS were down-regulated after Cu2+ exposure, while hemocyanin , MT , HSP70 and HSP90 were significantly up-regulated, implying these molecules may play vital role in Cu2+ detoxification of N. denticulate sinensis. Our results here provide research direction of heavy metal detoxification of N. denticulate sinensis , simultaneously enriched its genomic information. [Display omitted] • Transcriptome data of Neocaridina denticulate sinensis response to copper exposure. • 23,266 unigenes were assembled and annotated. • 16,423 DEGs were identified and functional enrichment analysis was carried out. • Eight DEGs were validated by qRT-PCR. [ABSTRACT FROM AUTHOR]

Arginine kinase (AK, EC 2.7.3.3) plays an important role in cells with high, fluctuating energy requirements. In invertebrates, AK is the major phosphagen kinase that modulates the energy metabolism. Here, the full-length cDNA sequence encoding arginine kinase (EcAK) was obtained from the Exopalaemon carinicauda. The complete nucleotide sequence of EcAK contained a 1068 bp open reading frame (ORF) encoding EcAK precursor of 355 amino acids. The genomic DNA fragment of EcAK with the corresponding cDNA sequence is composed of 4 exons and 3 introns. The domain architecture of the deduced EcAK protein contained an ATP-gua_PtransN domain and an ATP-gua_Ptrans domain. EcAK mRNA was predominantly expressed in the muscle. The expression of EcAK in the prawns challenged with Vibrio parahaemolyticus and Aeromonas hydrophila changed in a time-dependent manner. Then, EcAK was recombinantly expressed in Pichia pastoris and the purified recombinant EcAK had the same enzymatic characterization as AK from the muscle of Euphausia superba. In conclusion, EcAK may play the same biological activity in E. carinicauda as those from other crustaceans. Image 1 • EcAK was obtained from E. carinicauda and it is composed of 4 exons and 3 introns. • EcAK was predominantly expressed in muscle of E. carinicauda. • EcAK expression changed in a time-dependent manner after prawns were challenged with V. parahaemolyticus or A. hydrophila. • EcAK was recombinantly expressed in Pichia pastoris and the enzymatic characterization of recombinant EcAK was studied. [ABSTRACT FROM AUTHOR]

Trehalose, a nonreducing disaccharide, is present in a wide variety of organisms and plays a key role in many organisms under different stress conditions. In the study, the full-length cDNA sequence encoding trehalose-6-phosphate synthase (EcTPS) was obtained from Exopalaemon carinicauda. The complete nucleotide sequence of EcTPS contained a 2532 bp open reading frame (ORF) encoding a putative protein of 843 amino acids. The domain architecture of the deduced EcTPS contained a glycol_transf_20 domain and a trehalose_PPase domain. EcTPS mRNA was predominantly expressed in the hepatopancreas. The expression of EcTPS in the prawns challenged with Vibrio parahaemolyticus and Aeromonas hydrophila changed in a time-dependent manner. The function of EcTPS was also studied by double-strand RNA interference. The results showed that the knock-down of EcTPS increased the mortality of the Vibrio -challenged group and Aeromonas -challenged group compared with the control group. The present study provides some new insight into the immune function of the trehalose-6-phosphate synthase in prawns. • EcTPS was identified in E. carinicauda. • EcTPS was predominantly expressed in the hepatopancreas of E. carinicauda. • EcTPS was upregulated after the challenge with V. parahaemolyticus or A. hydrophila. • Knock-down of EcTPS increased the mortality of bacteria-challenged prawns. [ABSTRACT FROM AUTHOR]

Abstract The gC1qR is a ubiquitously expressed cell protein that interacts with the globular heads of C1q (gC1q) and many other ligands. In this study, one gC1qR homolog gene was obtained from Exopalaemon carinicauda and named EcgC1qR. The complete nucleotide sequence of EcgC1qR contained a 774 bp open reading frame (ORF) encoding EcgC1qR precursor of 257 amino acids. The deduced amino acid sequence of EcgC1qR revealed a 55-amino-acid-long mitochondrial targeting sequence at the N-terminal and a mitochondrial acidic matrix protein of 33 kDa (MAM33) domain. The genomic organization of EcgC1qR gene showed that EcgC1qR gene contained five exons and four introns. EcgC1qR could express in all of the detected tissues and its expression was much higher in hepatopancreas and hemocytes. The expression of EcgC1qR in the hepatopancreas of prawns challenged with Vibrio parahaemolyticus and Aeromonas hydrophila changed in a time-dependent manner. The expression of EcgC1qR in prawns challenged with V. parahaemolyticus was up-regulated at 6 h (p < 0.05), and significantly up-regulated at 12 h and 24 h (p < 0.01), and then returned to the control levels at 48 h post-challenge (p > 0.05). At the same time, the expression in Aeromonas -challenged group was significantly up-regulated at 6, 12 and 24 h. The recombinant EcgC1qR could inhibit the growth of two tested bacteria. In addition, we successfully deleted EcgC1qR gene through CRISPR/Cas9 technology and it was the first time to obtain the mutant of gC1qR homolog gene in crustacean. It's a great progress to study the biological function of gC1qR in crustacean in future. Graphical abstract Image 1 Highlights • The expression profiles of EcgC1qR was were demonstrated. • EcgC1qR was up-regulated after challenge with V. parahaemolyticus or A. hydrophila. • EcgC1qR was successfully deleted through CRISPR/Cas9. [ABSTRACT FROM AUTHOR]

Methyl farnesoate (MF) is considered the equivalent of JH in crustaceans and plays an essential role in many crucial physiological processes. It is believed that farnesyl pyrophosphate synthase (FPPS) plays an essential role in the biosynthesis of mevalonate, which is a branch of the JH/MF pathway. The full-length cDNA of FPPS (NdFPPS) from Neocaridina denticulata sinensis was isolated and characterized, and the deduced amino acid of NdFPPS contained a polyprenyl_synt domain. In addition to its ubiquitous tissue expression, NdFPPS was significantly expressed in the ovary. In vivo gene silencing with dsRNA interference was performed to further investigate the function of NdFPPS. An ovarian transcriptomic analysis of ds NdFPPS experimental and control groups was used to compare, annotate, and classify differentially expressed genes (DEGs). A total of 9230 DEGs were identified in the experimental and control groups based on FPKM values, of which 5082 were up-regulated genes and 4148 were down-regulated genes. 761 GO terms and 102 KEGG pathways were enriched for the DEGs. Our results suggest that NdFPPS might play an important role in ovarian development, however, further functional study is needed to elucidate physiological role of NdFPPS in reproduction. • NdFPPS gene was obtained from N. denticulata sinensis. • Distribution of NdFPPS mRNA detected in different tissues. • Knockdown of NdFPPS affects ovarian development. [ABSTRACT FROM AUTHOR]

• LPS treatment increases aquaporin 4 expression and cytokine secretion in astrocytes. • Lipoxin A4 reduces aquaporin 4 expression and inflammatory response in astrocytes. • AQP4 on astrocytes is possibly a target of the anti-inflammatory effect of LXA4. Aquaporin (AQP4) could be associated with inflammation, common in central nervous system diseases. We investigated the effect of lipoxin A4 (LXA4) on the activation of astrocytes, AQP4 expression, and inflammatory response induced by lipopolysaccharide (LPS). Astrocytes were cultured in vitro and changes in transcript and protein levels of AQP4, interleukin-1β (IL-1β), tumor necrosis factor-alpha (TNF-α), and cyclooxygenase-2 (COX-2), and protein levels of P38 and phospho-P38 were determined. The LPS group showed increased AQP4, IL-1β, TNF-α, and COX-2 levels, whereas they decreased in the LPS + LXA4 group, suggesting that LXA4 inhibits AQP4 expression. Furthermore, levels of phospho-P38 increased in the LPS group, but decreased in the LPS + LXA4 group. In conclusion, LXA4 alleviated the LPS-induced increase in AQP4 expression and inflammatory cytokine secretion by astrocytes, possibly by inhibiting P38 phosphorylation. For the first time, we found that LXA4 may inhibit the expression of inflammatory factors by regulating the expression of AQP4. AQP4 on astrocytes is likely to be the target of anti-inflammatory effect of LXA4. [ABSTRACT FROM AUTHOR]