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Novel MnCo 2 O 4 -discs and MnCo 2 O 4 -rings were respectively prepared through a facile hydrothermal approach with a post annealing treatment. These MnCo 2 O 4 -discs exhibited battery-type electrochemical response with a high capacity of 296.1C/g at 1 A/g in 2 M of KOH electrolyte. The assembled MnCo 2 O 4 -discs//AC asymmetric supercapacitor delivered a high energy density of 35.8 W h kg−1 at the power density of 927.5 W kg−1. [Display omitted] • Novel MnCo 2 O 4 -discs were hydrothermally prepared with a post annealing treatment. • A high specific capacity of 296.1C/g at 1 A/g was delivered. • Just a little capacity decay over 5000 cycles at a high current density of 6 A/g. • The ASC device delivered an energy density of 35.8 W h kg−1 at 927.5 W kg−1. Herein, porous MnCo 2 O 4 with disc-like (MnCo 2 O 4 -discs) and ring-like (MnCo 2 O 4 -rings) microstructures were respectively synthesized using an initial hydrothermal method at different temperatures and a calcination treatment in air. The electrochemical properties of these MnCo 2 O 4 materials were investigated in three-electrode and two-electrode systems, and as such, MnCo 2 O 4 presented a battery-like electrochemical response. The specific capacity of MnCo 2 O 4 -discs was determined to be 296.1C/g at 1 A/g, superior to 246.3C/g for MnCo 2 O 4 -rings. An asymmetric supercapacitor (ASC) was assembled with MnCo 2 O 4 as the cathode and activated carbon (AC) as the anode to evaluate the potential for practical application. The MnCo 2 O 4 -discs//AC ASC exhibited an energy density (E d) of 35.8 W h kg−1 at a power density (P d) of 927.5 W kg−1. For the MnCo 2 O 4 -rings//AC ASC, an inferior E d of 31.4 W h kg−1 under 890.9 W kg−1 was achieved. Furthermore, the two ASCs presented outstanding cyclic performance after 5000 cycles at 6 A/g. The exceptional properties of MnCo 2 O 4 microstructures can be applied to the assembly of ASC devices, which can have promising potential for application in electrochemical energy storage. This synthetic method is straightforward, cost-effective, and can be extended to fabricate similar electrode materials with superior electrochemical performance. [ABSTRACT FROM AUTHOR]

Endomesodermal cell fate specification and archenteron formation during gastrulation are tightly linked developmental processes in most metazoans. However, studies have shown that in the anthozoan cnidarian Nematostella vectensis , Wnt/β-catenin (cWnt) signalling-mediated endomesodermal cell fate specification can be experimentally uncoupled from Wnt/Planar Cell Polarity (PCP) signalling-mediated primary archenteron invagination. The upstream signalling mechanisms regulating cWnt signalling-dependent endomesoderm cell fate specification and Wnt/PCP signalling-mediated primary archenteron invagination in Nematostella embryos are not well understood. By screening for potential upstream mediators of cWnt and Wnt/PCP signalling, we identified two Nematostella Frizzled homologs that are expressed early in development. NvFzd1 is expressed maternally and in a broad pattern during early development while NvFzd10 is zygotically expressed at the animal pole in blastula stage embryos and is restricted to the invaginating cells of the presumptive endomesoderm. Molecular and morphological characterization of NvFzd1 and NvFzd10 knock-down phenotypes provide evidence for distinct regulatory roles for the two receptors in endomesoderm cell fate specification and primary archenteron invagination. These results provide further experimental evidence for the independent regulation of endomesodermal cell fate specification and primary archenteron invagination during gastrulation in Nematostella. Moreover, these results provide additional support for the previously proposed two-step model for the independent evolution of cWnt-mediated cell fate specification and Wnt/PCP-mediated primary archenteron invagination. [Display omitted] • Endomesoderm specification and gastrulation are tightly linked events in Bilateria. • These processes can be experimentally uncoupled in the cnidarian N. vectensis. • Nematostella primary gut invagination can occur without endomesoderm specification. • NvFzd1 regulates endomesoderm specification and NvFzd10 regulates gut invagination. • These results suggest that the two processes arose independently during evolution. [ABSTRACT FROM AUTHOR]

CoNi LDH nanostructures with large specific surface areas were prepared through a facile sonochemical approach in the solutions with different pH values. The CoNi LDH exhibited battery-type electrochemical response with the highest capacity of 740.8C/g at 1 A/g in 2 M of KOH electrolyte. The assembled CoNi LDH//AC hybrid supercapacitor delivered the highest energy density of 35.6 W h kg−1 at the power density of 781.1 W kg−1. [Display omitted] • CoNi LDH nanostructures with large surface area were sonochemically prepared. • A high specific capacity of 740.8C/g at 1 A/g was delivered. • Just a little capacity decay over 5000 cycles at a high current density of 8 A/g. • The HSC device delivered an energy density of 35.6 W h kg−1 at 781.1 W kg−1. Fabricating battery-type electrode materials with large specific surface area and mesopores is an efficient method for enhancing the electrochemical performance of supercapacitors. This method may provide more active sites for Faradic reactions and shorten the ion-diffusion paths. In this study, the CoNi layered double hydroxides (LDHs) with the morphology of nanoflowers and nanoflakes were prepared in solutions with pH values of 7.5 (CoNi LDH-7.5) and 8.5 (CoNi LDH-8.5) via a simple sonochemical approach. These CoNi LDHs possessed large specific surface areas and favourable electrochemical properties. The CoNi LDH-7.5 delivered a specific capacity of 740.8C/g at a current density of 1 A/g, surpassing CoNi LDH-8.5 with 668.1C/g. The hybrid supercapacitor (HSC) was assembled with activated carbon as the anode and CoNi LDH as the cathode to assess its practical application potential in the field of electrochemical energy storage. The CoNi LDH-7.5//AC HSC achieved the highest energy density of 35.6 W h kg−1 at a power density of 781.1 W kg−1. In addition, both HSCs exhibited little capacity decay over 5,000 cycles at a high current load of 8 A/g. These electrochemical properties of CoNi LDHs make them promising candidates for battery-type electrode materials. The current sonochemical method is simple and can be applied to the preparation of other LDHs-based electrode materials with favourable electrochemical performance. [ABSTRACT FROM AUTHOR]

In this study, an echinoderm tumor necrosis factor receptor named HLTNFR-16 was first cloned from the tropical sea cucumber Holothuria leucospilota. The full-length cDNA of HLTNFR-16 is 3675 bp in size, containing a 415 bp 5′-untranslated region (UTR), a 2024 bp 3′-UTR and a 1236 bp open reading frame (ORF) encoding a protein of 411 amino acids with a deduced molecular weight of 45.63 kDa. The HLTNFR-16 protein contains a signal peptide, four TNFR domains (the last three were identified as extracellular cysteine-rich domains), a transmembrane region and a death domain. Phylogenetic analysis showed that HLTNFR-16 was clustered into a clade with TNFR-16s in other species, indicating that this echinoderm TNFR may be a new member of the TNFR-16 subfamily. The results of TUNEL assay showed that the over expression of HLTNFR-16 could induce apoptosis in HEK293T cells. When HLTNFR-16 was silenced by siRNA, the apoptosis of sea cucumber coelomocytes induced by inactivated Vibrio harveyi was suppressed significantly, indicating that HLTNFR-16 is important for apoptosis induction. Additionally, luciferase reporter assay exhibited that the over-expressed HLTNFR-16 in HEK293T cells could activate the transcription factors nuclear factor-κB (NF-κB) and activator protein-1 (AP-1). Moreover, the secretion of proinflammatory cytokines interleukin (IL)-1β, IL-6 and IL-18 in HEK293T cells was increased by the over-expression of HLTNFR-16. This study provides evidences for the potential roles of sea cucumber TNFR in the innate immunity. • We identified a TNFR-16 from the tropical sea cucumber Holothuria leucospilota. • Over-expression of HLTNFR-16 could induce apoptosis in HEK293T cells. • The silencing of HLTNFR-16 could significantly suppress the apoptosis of sea cucumber coelomocytes induced by inactivated Vibrio harveyi. • Over-expressed HLTNFR-16 could activate the transcription factors nuclear factor-κB and activator protein-1. • Over-expressed HLTNFR-16 could induce the secretion of proinflammatory cytokines. [ABSTRACT FROM AUTHOR]

Microorganic pollutants (MOPs) in aquatic environment with low levels but high toxicity are harmful to ecosystem and human health. Fe(VI) has a dual-functional role in oxidation and coagulation, and can effectively remove MOPs, heavy metal, phosphate, particulates and colloids. Moreover, Fe(VI) can combine with traditional coagulants, or use as a pretreatment for membrane treatment because of its characters to generate nanoparticles by degradation in water. Based on the relevant toxicity experiments, Fe(VI) had been proved to be safe for the efficient treatment of MOPs. For better utilization of Fe(VI), its oxidation and coagulation mechanisms are summarized, and the knowledge about the control parameters, utilization methods, and toxicity effect for Fe(VI) application are reviewed in this paper. pH, different valences of iron, environmental substances, and other parameters are summarized in this study to clarify the important factors in the treatment of MOPs with Fe(VI). In the future study, aiming at cost reduction in Fe(VI) preparation, transportation and storage, enhancement of oxidation in the intermediate state, and better understanding the mechanism between interface and Fe(VI) oxidation will help promote the application of Fe(VI) in the removal of MOPs. This study offers guidelines for the application and development of Fe(VI) for the treatment of MOPs in aquatic environment. [Display omitted] • Oxidation and coagulation mechanisms on the removal of MOPs using Fe(VI) are reviewed. • Coagulation behavior of Fe(VI) differs from that of Fe(III) by producing Fe 2 O 3 /FeOOH particles. • pH, iron valence, and environmental substances are important factors. • The optimal pH is related to the pK a of MOPs. [ABSTRACT FROM AUTHOR]

Poly-U-binding factor 60 kDa (PUF60), also known as Ro RNA binding protein (RoBPI) and FBP interacting repressor (FIR), is a multifunctional protein that is involved in a variety of nuclear processes including pre-mRNA splicing, apoptosis and transcription regulation. In this study, the first echinoderm PUF60 named StmPUF60 was identified from sea cucumber ( Stichopus monotuberculatus ). The StmPUF60 cDNA is 4503 bp in length, containing a 5′-untranslated region (UTR) of 34 bp, a 3′-UTR of 2963 bp and an open reading frame (ORF) of 1506 bp that encoding a protein of 501 amino acids with a deduced molecular weight of 54.15 kDa and a predicted isoelectric point of 5.15. The putative StmPUF60 protein possesses all the main characteristics of known PUF60 proteins, including two RNA recognition motifs (RRM1 and RRM2), a C-terminal PUMP domain and two conserved nucleic acid-binding ribonucleoprotein sequences (RNP1 and RNP2). For the gene structure, StmPUF60 contains nine exons separated by eight introns. In addition, the highest level of StmPUF60 mRNA expression was noticed in the gonad, followed by coelomocytes, intestine, respiratory tree and body wall. In in vivo experiments, the expression of StmPUF60 mRNA in coelomocytes and intestine was significantly up-regulated by lipopolysaccharides (LPS) challenge, suggesting that the sea cucumber PUF60 might play critical roles in the innate immune defense against bacterial infections. Moreover, we further confirmed that overexpressed StmPUF60 could induce apoptosis, and this function of StmPUF60 may be one of the innate immune defense mechanisms for sea cucumber against pathogen infections. [ABSTRACT FROM AUTHOR]

In this study, a sea cucumber Fas-associated death domain (FADD) named HLFADD was first cloned from Holothuria leucospilota. The full-length cDNA of HLFADD is 2137 bp in size, containing a 116-bp 5′-untranslated region (UTR), a 1334-bp 3′-UTR and a 687-bp open reading frame (ORF) encoding a protein of 228 amino acids with a deduced molecular weight of 26.42 kDa. HLFADD protein contains a conserved death effector domain at its N-terminal and a conserved death domain at its C-terminal, structurally similar to its counterparts in vertebrates. The over-expressed HLFADD protein could induce apoptosis in HEK293 cells, suggesting a possible death receptor-mediated apoptosis pathway in echinoderms adapted with FADD. Moreover, HLFADD mRNA is ubiquitously expressed in all examined tissues, with the highest transcript level in the coelomocytes, followed by intestine. In vitro experiments performed in the H. leucospilota coelomocytes, the expression of HLFADD mRNA was significantly up-regulated by lipopolysaccharides (LPS) or polyriboinosinic-polyribocytidylic acid [poly (I:C)] challenge, suggesting that HLFADD might play important roles in the innate immune defense of sea cucumber against the invasion of bacteria and viruses. • A sea cucumber FADD was first cloned from Holothuria leucospilota. • The conserved death effector domain and death domain were found in H. leucospilota FADD. • HLFADD mRNA is widely expressed and up-regulated by immune challenge in coelomocytes. • Overexpression of HLFADD can induce apoptosis in HEK293 cells. [ABSTRACT FROM AUTHOR]

Abstract Intestinal microbiota homeostasis is crucial to the health of host. Pathogen invasion results in dynamics of microbiota composition and structure, disrupting their function in maintaining host health. WSSV is the most prevalent viral pathogen and is able to cause extremely high mortality in Litopenaeus vannamei. However, the changes of intestinal microbiota induced by WSSV are yet to be elucidated. In this study, we analyzed and compared the microbiota of healthy and WSSV-challenged shrimp intestines. Though the richness and diversity of microbiota was barely affected by WSSV, the abundance of predominant phyla like Proteobacteria and Fusobacteria were upregulated significantly, while Bacteroidetes and Tenericutes were significantly decreased in WSSV-infected shrimps. At the genus level, significant increase was observed in Photobacterium, Propionigenium and Arcobacter , as well as significant decrease in Candidatus Bacilloplasma and Flavobacterium in WSSV-infected shrimps. Additionally, metagenomic predictions by PICRUSt suggested that the altered microbiota was mainly related to metabolism, human diseases, genetic information processing, environmental information processing and cellular processes. These results suggested that the invasion of WSSV could impact intestinal microbiota composition and function in L. vannamei. Highlights • WSSV infection impacts intestinal microbiota composition in Litopenaeus vannamei. • WSSV upregulated the abundance of phyla Proteobacteria and Fusobacteria significantly. • Phyla Bacteroidetes and Tenericutes decreased significantly after WSSV infection. • WSSV changed abundance of some pathogenic bacteria within genus Arcobacter and Flavobacterium. • Predicted KEGG pathways related to metabolism and biological processes were altered by WSSV. [ABSTRACT FROM AUTHOR]

Abstract In this study, a myeloid differentiation factor 88 (MyD88) named as HLMyD88 was identified from the sea cucumber Holothuria leucospilota. The full-length cDNA of HLMyD88 is 4797 bp in size, containing a 227 bp 5′-untranslated region (UTR), a 3721 bp 3′-UTR and an 849 bp open reading frame (ORF) encoding a protein of 282 amino acids with a deduced molecular weight of 32.25 kDa HLMyD88 contains an N-terminal death domain and a C-terminal Toll/interluekin-1 receptor (TIR) domain with three highly conserved sequence motifs named as Box 1, Box 2 and Box 3. The results of luciferase reporter assay showed that over-expressed HLMyD88 in HEK293T cells could activate the transcription factors nuclear factor-κB (NF-κB) and activator protein 1 (AP-1). Additionally, the secretion of proinflammatory cytokines IL-1β and TNF-α in the HEK293T cells was increased by over-expressed HLMyD88, indicating the potential role of HLMyD88 in the innate immunity of sea cucumber. Moreover, we further confirmed that over-expressed HLMyD88 could also induce apoptosis. Highlights • We identified an MyD88 from the tropical sea cucumber Holothuria leucospilota. • The conserved death domain and TIR domain were found in H. leucospilota MyD88. • Over-expressed HLMyD88 could activate the transcription factors nuclear factor-κB and activator protein 1. • Over-expressed HLMyD88 could induce the secretion of proinflammatory cytokines IL-1β and TNF-α. • Overexpression of HLMyD88 can induce apoptosis in HEK293T cells. [ABSTRACT FROM AUTHOR]

In this study, a novel caspase-6 named HLcaspase-6 was identified from sea cucumber Holothuria leucospilota . The full-length cDNA of HLcaspase-6 is 2195 bp in size, containing a 126 bp 5′-untranslated region (UTR), a 1043 bp 3′-UTR and a 1026 bp open reading frame (ORF) encoding a protein of 341 amino acids with a deduced molecular weight of 38.57 kDa. HLcaspase-6 contains the common signatures of the caspase family, including the conserved pentapeptide motif QACRG, as well as the P20 and P10 domains. In addition, HLcaspase-6 contains a short pro-domain. HLcaspase- 6 mRNA is ubiquitously expressed in all tissues examined, with the highest transcript level in the intestine, followed by coelomocytes. In in vitro experiments, the expression of HLcaspase- 6 mRNA in coelomocytes was significantly up-regulated by lipopolysaccharides (LPS) or polyriboinosinic-polyribocytidylic acid [poly (I:C)] challenge, suggesting that HLcaspase-6 might play important roles in the innate immune defense of sea cucumber against bacterial and viral infections. Moreover, we further confirmed that overexpression of HLcaspase-6 could induce apoptosis and activate the p53 signal pathway. [ABSTRACT FROM AUTHOR]

In this study, the first tropical sea cucumber caspase-8 named HLcaspase-8 was identified from Holothuria leucospilota . The full-length cDNA of HLcaspase-8 is 2293 bp in size, containing a 245 bp 5′-untranslated region (UTR), a 521 bp 3′-UTR and a 1527 bp open reading frame (ORF) encoding a protein of 508 amino acids with a deduced molecular weight of 57.47 kDa. Besides the common signatures of caspase family including conserved cysteine active site pentapeptide motif QACQG, P20 domain and P10 domain, HLcaspase-8 also contains a characteristic DED domain. The over-expression of HLcaspase-8 in HEK293T cells showed that HLcaspase-8 protein could induce apoptosis and the apoptosis could be promoted by TNF-α, indicating that the apoptosis induced by HLcaspase-8 might also be triggered via a receptor-mediated pathway. Moreover, the expression of HLcaspase-8 in in vitro experiments performed in coelomocytes was significantly up-regulated by lipopolysaccharides (LPS) or polyriboinosinic-polyribocytidylic Acid [poly (I:C)] challenge, suggesting that the sea cucumber caspase-8 might play some important roles in the innate immune defense against bacterial and viral infections. [ABSTRACT FROM AUTHOR]

A novel antistasin/WAP-like serine protease inhibitor, named as StmAW-SPI, was identified from sea cucumber ( Stichopus monotuberculatus ) and functionally characterized in this study. The full-length cDNA of StmAW-SPI is 1917 bp in length with a 72 bp 5’-untranslated region (UTR), a 294 bp 3′-UTR and a 1551 bp open reading frame (ORF) encoding a protein of 516 amino acids with a deduced molecular weight of 54.56 kDa. The StmAW-SPI protein has 5-fold internal repeats (IRs) of antistasin domain and 6-fold IRs of WAP domain. For the gene structure, StmAW-SPI contains 10 exons separated by 9 introns. The StmAW-SPI mRNA expression pattern was determined using quantitative real-time PCR. The highest level of StmAW-SPI was found in the intestine, followed by coelomocytes, gonad, body wall and respiratory tree. The StmAW-SPI expressions were significantly up-regulated after polyriboinosinic polyribocytidylic acid [Poly (I:C)] or lipopolysaccharides (LPS) challenge in in vitro experiments performed in primary coelomocytes. In addition, the serine protease inhibitory activity and bacterial protease inhibitory activity of StmAW-SPI were examined, and the antibacterial activity was also demonstrated in this study. Our study, as a whole, suggested that StmAW-SPI might play a critical role in the innate immune defense of sea cucumber against microbial infections, by not only inactivating the serine protease but also inhibiting the growth of pathogens. [ABSTRACT FROM AUTHOR]

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a multifunctional protein that widely exists in eukaryotic species. In this study, two PCSK9 paralogs, named StmPCSK9-1 and StmPCSK9-2, were identified from the tropical sea cucumber ( Stichopus monotuberculatus ). The cDNAs of StmPCSK9-1 and StmPCSK9-2 are 1330 kb and 1508 kb in size, respectively. The open reading frames (ORF) for StmPCSK9-1 and StmPCSK9-2 cDNAs are 1128 and 1167 bp in length, encoding the proteins of 375 and 388 amino acids with the deduced molecular weights of 38.76 and 41.07 kDa, respectively. In accord with other members in PCSK9 family, the two StmPCSK9 paralogs possessed the inhibitor_I9 and peptidase_S8 functional domains, seven active sites, a catalytic triad and two calcium binding sites. For the gene structure, the splicing of the two StmPCSK9 paralogs was relatively conserved. In addition, the mRNA expression of StmPCSK9-1 and StmPCSK9-2 was only detected in the sea cucumber intestine and coelomocytes, and the expression levels of both the two StmPCSK9 paralogs were higher in intestine. Moreover, StmPCSK9-2 was found to be a cytoplasm protein without signal peptide, and show no response to the immune challenge. On the contrary, StmPCSK9-1 was a secreted protein and the transcriptional expression of StmPCSK9-1 was significantly up-regulated by lipopolysaccharides (LPS) treatment and slightly down-regulated by polyriboinosinic polyribocytidylic acid [Poly (I:C)] challenge in in vitro experiments performed in the cultural primary coelomocytes, suggesting that the StmPCSK9-1 may play critical roles in the innate immune defense of sea cucumber, S. monotuberculatus , against bacterial and/or viral infections. [ABSTRACT FROM AUTHOR]

Abstract: Vibrio alginolyticus has been confirmed as an important pathogen for aquatic animals. However, the pathogenic mechanism of V. alginolyticus is not completely understood. A total of 31 isolates of V. alginolyticus from sea water, fish and shrimp on the mariculture systems were fingerprinted by pulsed-field gel electrophoresis. The pathogenicity of these isolates was tested by challenge and the 21 genes associated with the virulence of Vibrio cholerae or Vibrio parahaemolyticus were examined in V. alginolyticus using PCR. The results showed that the 31 V. alginolyticus isolates belonged to 26 PFGE genotypes and the isolates from different source had different genotypes. Nine of the 31 isolates were confirmed as pathogenic strains by challenge. Moreover, 12 vibrio virulence genes were detected in this study. Of the detected genes, VCtoxR, VCtoxS, hlyA, VPtoxR and tlh were found in both pathogenic and non-pathogenic isolates. However, the other 7 virulence genes, ctxB, zot, tagA, stn, sto, tdh and trh, were only present in pathogenic isolates. Analysis of the relationship between virulence associated genes and pathogenicity of V. alginolyticus provides a possible explanation that the pathogenic mechanism of V. alginolyticus might be similar to that of V. parahaemolyticus instead of V. cholerae. [Copyright &y& Elsevier]