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The carapace of arthropods not only served as a protective exoskeleton, but also performed a wide range of physiological and biochemical functions. In this study, we preliminarily investigated the protein and metabolite components of the carapace of Pacific white shrimp Litopenaeus vannamei and their biological functions, focusing on their roles in the process of innate immunity. The structure of the carapace was analyzed by scanning electron microscopy (SEM), while quantitative proteomics and metabolomics were used to investigate its components and functions. A total of 1,108 proteins and 725 metabolites were identified in the carapace of L. vannamei, including 69 immune-related proteins and 9 immune-related metabolites. These diverse components are involved in metabolism, environmental responses and immunity, enriched in pathways such as Toll-like receptor, IMD, NOD-like receptor and melanogenesis, demonstrating the shrimp's ability to combat pathogens through both active and passive immune mechanisms. In conclusion, this study demonstrated that shrimp carapace plays an essential role in the innate immune process. [ABSTRACT FROM AUTHOR]

Amylase is the main digestive enzyme in crustaceans, and plays extremely important roles in metabolism, growth and development. Some studies have also shown that amylase may play a role in the immune defense system of aquatic organisms. In this study, a novel a-amylase gene (designated as EsAMY) was cloned and identified from Chinese mitten crab Eriocheir sinensis. The complete cDNA sequence of EsAMY contained a 5' untranslated region (UTR) of 39 bp, a 3' UTR of 70 bp with a polyA tail, and an open reading frame (ORF) of 1554 bp encoding a polypeptide of 517 amino acids with the predicted molecular weight of 56.9 kDa. The deduced amino acids sequence of EsAMY contained conserved cysteine site, active catalytic site, calcium binding site and chloride binding site, which was similar with previously identified a-amylase genes in other species. Quantitative real-time PCR (qPCR) analysis showed that EsAMY transcripts were detectable in all the tested tissues, with the highest mRNA expression levels in hemocytes. Both Aeromonas hydrophila and polybrominated diphenyl ether-47 (BDE-47) stimulation could significantly induce the mRNA expression of EsAMY gene in hemocytes, and its responses to A. hydrophila was more intense than those of BDE-47. These results indicate that EsAMY is a new member of the amylase family and may be involved in the immune response of Chinese mitten crab to both invasive microorganisms and external pollutant stimulation. [ABSTRACT FROM AUTHOR]

PDGF/VEGF factors are closely associated with immune defense systems. In this study, a PDGF/VEGF related factor gene (designated as PtPVF) from swimming crab Portunus trituberculatus was identified and analyzed. Its full-length cDNA is 1320 bp, containing an open reading frame (ORF) of 582 bp, 5' untranslated regions (UTR) of 105 bp and 3' UTR of 633 bp, which encoded a polypeptide of 193 amino acid residues. The deduced amino acid sequence of PtPVF contained a signal peptide, a typical PDGF/VEGF domain, and a cysteine knot motif (CXCXC). Quantitative real-time PCR analysis demonstrated that the mRNA of PtPVF was detectable in gills, gonads, heart, hemocytes, hepatopancreas, intestines, muscles, optic stalk, stomach, and the highest level was found in hemocytes, followed by gill and hepatopancreas. After stimulation by Vibrio alginolyticus, pentachlorophenol (PCP) or cadmium chloride (CdCl2), the relative mRNA expression levels of PtPVF in hemocytes reached their respective peaks at 3 h, 6 h and 6 h, and 36.61-fold, 3.06-fold and 21.26-fold compared with the original level, respectively, and the respond to V. alginolyticus and CdCl2 is earlier than to PCP, while under the challenge of V. alginolyticus and CdCl2, the mRNA expression level of PtPVF was significantly higher than that of PCP stimulation. Furthermore, the mRNA expression level of PtPVF first decreased at 3 h and then increased rapidly to a peak at 6 h after PCP challenge. All these results demonstrated that PtPVF might be involved in the response to invading pathogens and environmental pollution stimulants of P. trituberculatus. [ABSTRACT FROM AUTHOR]

The pollution of phthalic acid esters (PAEs) in edible oils is a serious problem. In the current study, we attempt to remove dibutyl phthalate ester (DBP) from evening primrose oil (EPO) with modified activated clay. The activated clay, commonly used for de-coloration in the oil refining process, was modified by chitosan and hexadecyl trimethyl ammonium bromide (CTAB). The modifications were characterized by SEM, XRD, and FT-IR. We further tested the DBP adsorption capacity of CTAB/chitosan-clay and found that the removal rate was 27.56% which was 3.24 times higher than with pristine activated clay. In addition, the CTAB/chitosan-clay composite treatment had no significant effect on the quality of evening primrose oil. In summary, the CTAB/chitosan-clay composite has a stronger DBP adsorption capacity and can be used as a new adsorbent for removing DBP during the de-coloration process of evening primrose oil. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) is a product of normal metabolism of aerobic cells, but excess ROS is harmful to the organism. Copper/zinc superoxide dismutase (Cu-Zn SOD) is a metalloenzyme for scavenging ROS. In this study, two extracellular Cu-Zn SOD genes (designated as LvEcSOD1 and LvEcSOD2) were cloned by rapid amplification of cDNA ends (RACE) technique. The cDNA length of LvEcSOD1 is 801 bp, with an open reading frame (ORF) of 555 bp, encoding a peptide of 184 amino acids. The cDNA length of LvEcSOD2 is 934 bp with an ORF of 678 bp, encoding a peptide of 225 amino acids. The predicted amino acid sequences of the two LvEcSOD both contained conserved four Cu2+ binding sites and four Zn2+ binding sites. The mRNA scripts of LvEcSOD1 and LvEcSOD2 were widely detectable in the eyestalk, gill, gonad, heart, hemocytes, hepatopancreas, intestine, muscle, nerve, and stomach of Litopenaeus vannamei. Both LvEcSOD1 and LvEcSOD2 exhibited the highest expression levels in hemocytes and hepatopancreas. After the white shrimp was stimulated by white spot syndrome virus (WSSV) or Vibrio parahaemolyticus, the mRNA expression levels of these two genes were up-regulated to varying degrees. The relative expression level of LvEcSOD2 was significantly increased after stimulation by two pathogenic microorganisms, which was generally later than that of LvEcSOD1. These results indicated that the two genes are both involved in the innate immunity of L. vannamei with different functions. [ABSTRACT FROM AUTHOR]

Based on lots of results, the QM protein was proposed to be a tumor suppressor, and facilitate in the innate immune responses, especially the prophenoloxidase (proPO) activation system. In the present study, a cDNA of 761 bp for the QM of Chinese shrimp, Fenneropenaeus chinensis (designated as FcQM) was cloned via rapid amplification of cDNA ends (RACE) technique. The complete cDNA sequence of FcQM contained an open reading frame (ORF) of 663 bp, 5' untranslated regions (UTR) of 42 bp and 3' UTR of 56 bp, which encoded a polypeptide of 155 amino acid residues. The analysis of the peptide sequence of FcQM revealed that FcQM sequence contained a Ribosomal_L16 domain, an SH3-binding motif, an N-acylation site, two putative antibiotic binding sites, two putative protein kinase C phosphorylation sites and two acylamidation sites, which shared over 80 % similarity with previously identified QM protein genes. Quantitative real-time PCR (qRT-PCR) results showed that the transcript of FcQM was extensively distributed in all the tested tissues and most highly expressed in hemocytes and hepatopancreas. After challenged with Vibrio anguillarum or white spot syndrome virus (WSSV), the FcQM transcripts were significantly increased (p < 0.05) both in hepatopancreas and hemocytes. Hence, the analysis of sequence and transcription suggested that FcQM might play crucial roles responses to bacterial and viral invasion in innate immunity of arthropods. This study is the first report of the QM protein gene from F. chinensis, which would enrich the understanding of the innate immune defense mechanism in shrimp. [ABSTRACT FROM AUTHOR]

Cyclophilin A (CypA), a key member of the immunophilin family, is the most abundantly expressed one among the 16 identified cyclophilins. Besides acting as an intracellular receptor for cyclosporine A, CypA plays a vital role in various pathological responses such as inflammation and microbial infections. In the present study, the full-length cDNA of Fenneropenaeus chinensis CypA (FcCypA) was cloned by RACE technique. The complete sequence of FcCypA cDNA contained a 5' untranslated region (UTR) of 33 bp, a 3' UTR of 341 bp with a polyA tail, and an open reading frame (ORF) of 495 bp encoding a polypeptide of 164 amino acids with the predicted molecular weight of 17.70 kDa. The amino acid sequence of CypA has a typical peptidyl prolyl cis-trans isomerase family tag sequence (YKGSTFHRVIPNFMCQGG) as those of other species. The mRNA transcripts of FcCypA were constitutively expressed in all the tested tissues, including eyestalk, gill, gonad, heart, hemocytes, hepatopancreas, intestine, muscle, nerve and stomach, with the highest expression level in hepatopancreas. The mRNA expression profiles of FcCypA in hemocytes and hepatopancreas could be significantly induced by the stimulation of Vibrio anguillarum suspension and white spot syndrome virus (WSSV) stock, which verifies that CypA has an effect on viral and bacterial infection in shrimps. These results indicate that CypA may be involved in the innate immunity, biological immune response and physiological stress response of Chinese shrimps. [ABSTRACT FROM AUTHOR]

The aim of the study was to monitor the effects of exogenous geniposide (GD) on maize (Zea mays L.) and explore the mechanisms through which it mitigates saline-alkali stress to provide a theoretical basis for revealing the growth physiology and chemical regulation processes in maize. The control (CK) received nutrient solution culture while the group under saline-alkali stress(SAS) received 150mmol L-1 saline-alkali solution (molar concentration ratio NaCl:Na2SO4:NaHCO3:Na2CO3=1:9:9:1). ‘Jilong2’ (saline-alkali tolerant) and ‘Xinxuan58’ (saline-alkali sensitive) were chosen as experimental materials and were cultivated with hydroponic method. Maize received the saline-alkali solution 12 hours after GD treatment and saline-alkali solution was administered 3 times, every 12 hours. The GD and saline-alkali solution group constituted the S+G treatment which promoted maize and a significant increase was observed in fresh and dry weights, plant height and photosynthetic enzymes in the leaf along with a significant decrease in the root to shoot ratio compared with saline-alkali treatment. The indoleacetic acid (IAA), zeatin-riboside (ZR), gibberellin (GA), superoxide radical (O2-) generation rate, malonaldehy (MDA) and hydrogen peroxide (H2O2) levels in roots were significantly lower than in the S+G treatment under saline-alkali stress, while the level of abscisic acid (ABA) and the activity of antioxidative enzymes increased. [ABSTRACT FROM AUTHOR]