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1.
J Am Chem Soc ; 144(1): 515-526, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34935372

RESUMO

Organozinc reagents are among the most commonly used organometallic reagents in modern synthetic chemistry, and multifunctionalized organozinc reagents can be synthesized from structurally simple, readily available ones by means of alkyne carbozincation. However, this method suffers from poor tolerance for terminal alkynes, and transformation of the newly introduced organic groups is difficult, which limits its applications. Herein, we report a method for vinylzincation of terminal alkynes catalyzed by newly developed iron catalysts bearing 1,10-phenanthroline-imine ligands. This method provides efficient access to novel organozinc reagents with a diverse array of structures and functional groups from readily available vinylzinc reagents and terminal alkynes. The method features excellent functional group tolerance (tolerated functional groups include amino, amide, cyano, ester, hydroxyl, sulfonyl, acetal, phosphono, pyridyl), a good substrate scope (suitable terminal alkynes include aryl, alkenyl, and alkyl acetylenes bearing various functional groups), and high chemoselectivity, regioselectivity, and stereoselectivity. The method could significantly improve the synthetic efficiency of various important bioactive molecules, including vitamin A. Mechanistic studies indicate that the new iron-1,10-phenanthroline-imine catalysts developed in this study have an extremely crowded reaction pocket, which promotes efficient transfer of the vinyl group to the alkynes, disfavors substitution reactions between the zinc reagent and the terminal C-H bond of the alkynes, and prevents the further reactions of the products. Our findings show that iron catalysts can be superior to other metal catalysts in terms of activity, chemoselectivity, regioselectivity, and stereoselectivity when suitable ligands are used.

2.
Org Biomol Chem ; 20(11): 2227-2232, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35237774

RESUMO

Herein is reported the first example of ring opening and skeletal reconstruction of 3-vinyl benzofuranone-chromones 1 as versatile synthons, which can react with ammonia or primary aliphatic amines as binucleophiles, for the eco-friendly and atom-economical synthesis of diverse and functionalized 2-pyridones 3 with potential biological activity in good to excellent yields (77-93%). When using optically active 1,2-diphenylethylenediamine 2 as the binucleophile, the in situ generated 2-pyridone intermediates are successfully transformed to novel optically active functionalized imidazoline derivatives 4 with high efficiency (up to 87% yield). In particular, this is the first report on the catalyst-free intramolecular cyclization occurring between an amide and a primary aliphatic amine for the construction of imidazoline molecules.


Assuntos
Cromonas , Imidazolinas , Aminas , Catálise , Piridonas
3.
Microvasc Res ; 134: 104120, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33309645

RESUMO

INTRODUCTION AND OBJECTIVES: Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death around the world. Despite improvement in the prevention and treatment of HCC, the clinical prognosis is still poor with increasing mortality. Non-coding RNAs play pivotal roles in HCC oncogenesis, but the detailed mechanism is poorly known. Therefore, the functions and interaction of lncRNA NORAD and miR-211-5p in HCC was investigated in this study. METHODS: Quantitative real-time PCR method was used to analyze the expression of NORAD and miR-211-5p in clinical HCC tissues and cultured cell lines. Knockdown of NORAD and overexpression of miR-211-5p were then carried in HCC cells. Moreover, bioinformatics analysis and luciferase report assays were further employed to analyze the interaction between miR-211-5p and NORAD or FOXD1. RESULTS: Increased lncRNA NORAD and decreased miR-211-5p expression were first detected in HCC compared with the peritumorial area. Further studies showed that knockdown of NORAD or overexpression of miR-211-5p impaired the proliferation, migration and angiogenesis of HCC cells. Mechanistically, we found that NORAD functions as a sponge for miR-211-5p. Moreover, it was revealed that decreased miR-211-5p induced the expression of FOXD1 as well as its downstream target VEGF-A, thereby contributes to enhanced angiogenesis of HCC. CONCLUSION: Elevated NORAD works as a sponge for miR-211-5p in HCC, thus release the inhibition effect of the latter on its downstream target FOXD1 and VEGF-A, which finally promotes angiogenesis. These results provide new insights into the interaction between NORAD and miR-211-5p in HCC and their potential usage as targets for the development of novel therapeutics against HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Movimento Celular , Proliferação de Células , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Neovascularização Fisiológica , RNA Longo não Codificante/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/genética , Invasividade Neoplásica , RNA Longo não Codificante/genética , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/genética
4.
Ecotoxicology ; 30(5): 954-965, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33864550

RESUMO

Clofibric acid (CFA), a drug and personal care product, has been identified as ubiquitous in the aquatic system and surface water, causing pollution to the environment. In this study, after environmental (4 µg/L) levels of CFA challenge, the LvFABP, LvACS gene expressions, total haemocyte count (THC), relative enzymes (SOD1 and GST) activities in Litopenaeus vannamei were observed to decrease. In the meantime LvFATP, LvRXR expression and the level of NEFA were upregulated in L. vannamei body. LvFABP expression in vivo was knocked down by dsRNA-mediated RNA interference (RNAi), which led to significantly decreased levels of PPARα (including LvFATP, LvRXR and LvACS). When exposed to environmental CFA after 4 days, LvFABP knocked down group had a sharp upregulation of LvFATP, LvRXR, LvACS expression, GST activity and NEFA amount, following decreased THC and SOD1 activity. These results suggested that environmental concentration CFA may have some toxicological effect on L. vannamei, following fatty acids metabolism and oxidative stress responses by LvFABP via the PPARα/RXR signaling pathway, including LvFATP, LvRXR and LvACS.


Assuntos
PPAR alfa , Penaeidae , Animais , Ácido Clofíbrico , Exposição Ambiental , Ácidos Graxos , Estresse Oxidativo , PPAR alfa/genética , Transdução de Sinais
5.
Fish Shellfish Immunol ; 90: 404-412, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31077847

RESUMO

MicroRNAs (miRNAs) are a kind of small non-coding RNAs that have been reported to play a vital role in mediating host-pathogen interactions. High-throughput sequencing technology was applied to identify and illuminate mRNAs and miRNAs from grouper infected with Vibrio alginolyticus. The KEGG pathway enrichment analysis showed that the most significate DEGs are associated with Toll-like receptor signaling pathway and NOD-like receptor signaling pathway. We obtained 374 known miRNAs and 116 novel miRNAs. During them, there are 31 up-regulated miRNAs and 93 down-regulated miRNAs. miRNA-mRNA GO and KEGG analysis show that there are 90 miRNAs associated with the immune system. The target genes of immune-related miRNAs (miR-142, miR-146, miR-150, miR-155, miR-203, miR-205, miR-24, miR-31) and genes (CD80, IL-2, AMPK, PI3K) in Epinephelus coioddes were predicted and validated. This study provides an opportunity to further understanding the molecular mechanisms especially the immune system of miRNA regulation in Epinephelus coioddes host-pathogen interactions.


Assuntos
Bass/genética , Bass/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Animais , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Vibrioses/imunologia , Vibrioses/veterinária , Vibrio alginolyticus/fisiologia
6.
Fish Shellfish Immunol ; 84: 8-19, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30261298

RESUMO

Complement 1 inhibitor (C1INH) serving as a multifunctional factor can participate in the regulation of complement cascades and attenuate the activation of various proteases. In this study, we obtained EcC1INH cDNA and the tissue-specific analysis indicate that the highest expression level of EcC1INH mRNA was detected in liver. Moreover, Vibrio alginolyticus challenge can significantly increase EcC1INH mRNA expression in liver and kidney. N-terminal domain of EcC1INH could decrease LPS binding activity to cell surface, while loss of positively charged residues (PCRs) Arg21, His22, Lys50, Arg61 in N-terminal domain of EcC1INH can significantly reduce its interaction with LPS. Furthermore, LPS injection experiment indicated that the binding of EcC1INH N-terminal domain to LPS can antagonize LPS-induced inflammatory signaling pathway and attenuate the production of proinflammatory cytokines in vivo, indicating that EcC1INH was involved in negative regulation of inflammatory response.


Assuntos
Proteína Inibidora do Complemento C1 , Proteínas de Peixes , Perciformes , Animais , Proteína Inibidora do Complemento C1/genética , Proteína Inibidora do Complemento C1/imunologia , Doenças dos Peixes/genética , Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Lipopolissacarídeos/farmacologia , Fígado/metabolismo , Perciformes/genética , Perciformes/imunologia , Domínios Proteicos , Vibrioses/genética , Vibrioses/imunologia , Vibrioses/veterinária , Vibrio alginolyticus
7.
Fish Shellfish Immunol ; 89: 486-497, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30980917

RESUMO

CD59, a multifunctional glycoprotein, not only plays a regulatory role in complement cascades, but also participates in modulation of teleostean immunity. In this study, full length sequence of EcCD59 was obtained, comprising a 5'UTR of 163 bp, an ORF of 354 bp and a 3'UTR of 559 bp. EcCD59 gene encoded a polypeptide of 117 amino acids. Tissue-specific analysis revealed that the highest expression of EcCD59 mRNA was observed in muscle. Vibrio alginolyticus challenge can significantly increase EcCD59 mRNA expression in liver, kidney and spleen. EcCD59 distribution was detected by a combined approach using GFP-overexpression, immunofluorescence and ELISA assay, indicating that EcCD59 may be predominantly aggregated in cellular membrane. Both EcCD59 and EcCD59delGPI can directly bind to V. alginolyticus and decrease the in vitro growth of V. alginolyticus. Additionally, vibrio injection experiment indicated that the binding of EcCD59 or EcCD59delGPI to V. alginolyticus can restrict its growth rate in vivo. In this study, we found that EcCD59 may be involved in immune defense against vibrio infection in a complement-independent manner.


Assuntos
Bass/genética , Bass/imunologia , Antígenos CD59/genética , Antígenos CD59/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Antígenos CD59/química , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Filogenia , Alinhamento de Sequência/veterinária , Vibrioses/imunologia , Vibrioses/veterinária , Vibrio alginolyticus/crescimento & desenvolvimento , Vibrio alginolyticus/fisiologia
8.
Fish Shellfish Immunol ; 76: 355-367, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29544772

RESUMO

It is well known that PI3K regulates various processes in mammalian cells by generating a secondary messenger that later activates AKT. However, its innate immune function in crustaceans remains unclear. We report the characterization of Litopenaeus vannamei PI3K (LvPI3K) for investigating how PI3K participates in the innate immunity of crustaceans. Full-length LvPI3K cDNA was 3357 bp long, with a 3222 bp open reading frame (ORF) that encodes a putative protein of 1292 amino acids. The PI3K catalytic domain (PI3Kc) of LvPI3K was found to be rather conserved when the PI3Ks from other species were analyzed. The LvPI3K protein was shown to be localized to the cytoplasm of Drosophila S2 cells, while LvPI3K mRNA was ubiquitously expressed in healthy L. vannamei, with the highest expression found in hemolymph. A dual luciferase reporter gene assay demonstrated that LvPI3K overexpression activated the promoter of antibacterial peptide LvPEN4 in a dose-dependent manner. However, the addition of PDTC, a specific inhibitor of NF-κB, suppressed the LvPI3K-induced LvPEN4 promoter activation. Moreover, Vibrio alginolyticus challenge induced a rapid up-regulation of LvPI3K expression. Further experiments showed that LvPI3K silencing in shrimp challenged with V. alginolyticus significantly increased Vibrio number, ROS production and DNA damage in the hemolymph, as well as significantly decreased total hemocyte count. The mRNA levels of certain molecules related to LvPI3K signaling, such as LvAKT and LvPEN4, also decreased following LvPI3K silencing. Taken together, these results suggest that LvPI3K regulates the downstream signal component LvPEN4 and functions in V. alginolyticus resistance.


Assuntos
Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Penaeidae/genética , Penaeidae/imunologia , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/imunologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Perfilação da Expressão Gênica , Fosfatidilinositol 3-Quinases/química , Filogenia , Alinhamento de Sequência , Vibrio alginolyticus/fisiologia
9.
Fish Shellfish Immunol ; 83: 190-204, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30195911

RESUMO

Nucleotide excision repair (NER) removes many different types of DNA lesions, and NER related host factors are reported to aid recovery steps during viral integration. Here, we report the identification and characterization of a DNA repair gene Rad23 from Litopenaeus vannamei and explore its role in innate immunity of crustaceans. LvRad23 contains a1149 bp open reading frame (ORF) which encodes a 382 amino acids protein with predicted theoretical isoelectric point of 4.21. LvRad23 was ubiquitously expressed in the muscle, eyestalk, gill, stomach, heart, legs, intestine, and hepatopancreas in order from high to low and LvRad23 protein was showed to be located in the cytoplasm of Drosophila S2 cells. The homology analysis showed that it has a high sequence homology with Rad23 protein from Marsupenaeus japonicus. Vibrio alginolyticus challenge induced a remarkable up-regulation of LvRad23 mRNA in hepatopancreas. Knocking down LvRad23can interfere the NER pathway by down regulating the expression of replication protein A (RPA) and proliferating cell nuclear antigen (PCNA). However it didn't cause any significant difference on total hemocyte count (THC) between LvRad23-silenced and non-silenced group.LvRad23-silenced then challenge with V. alginolyticus inducing high level of reactive oxygen species (ROS) and DNA damage in hemolymph. As well as decreased THC, which seriously diminished the innate immune system of L. vannamei. Meanwhile, the NER pathway was reactived by enhancing the expression of LvRad23 and promoting the production of LvPCNA to resist apoptosis and maintain proliferation of hemolymph cells in the later stage. Our results suggest that LvRad23 plays a vital role in shrimp specific immune response to V. alginolytcus through its participation in NER pathway.


Assuntos
Enzimas Reparadoras do DNA/genética , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Penaeidae/genética , Penaeidae/microbiologia , Vibrio alginolyticus , Animais , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Enzimas Reparadoras do DNA/metabolismo , DNA Complementar/genética , Proteínas de Ligação a DNA/metabolismo
10.
Infect Immun ; 84(1): 2-10, 2016 01.
Artigo em Inglês | MEDLINE | ID: mdl-26459509

RESUMO

The type III secretion system (T3SS) of Edwardsiella tarda is crucial for its intracellular survival and pathogenesis in fish. The orf13 gene (escE) of E. tarda is located 84 nucleotides (nt) upstream of esrC in the T3SS gene cluster. We found that EscE is secreted and translocated in a T3SS-dependent manner and that amino acids 2 to 15 in the N terminus were required for a completely functional T3SS in E. tarda. Deletion of escE abolished the secretion of T3SS translocators, as well as the secretion and translocation of T3SS effectors, but did not influence their intracellular protein levels in E. tarda. Complementation of the escE mutant with a secretion-incompetent EscE derivative restored the secretion of translocators and effectors. Interestingly, the effectors that were secreted and translocated were positively correlated with the EscE protein level in E. tarda. The escE mutant was attenuated in the blue gourami fish infection model, as its 50% lethal dose (LD50) increased to 4 times that of the wild type. The survival rate of the escE mutant-strain-infected fish was 69%, which was much higher than that of the fish infected with the wild-type bacteria (6%). Overall, EscE represents a secreted T3SS regulator that controls effector injection and translocator secretion, thus contributing to E. tarda pathogenesis in fish. The homology of EscE within the T3SSs of other bacterial species suggests that the mechanism of secretion and translocation control used by E. tarda may be commonly used by other bacterial pathogens.


Assuntos
Proteínas de Bactérias/genética , Edwardsiella tarda/patogenicidade , Doenças dos Peixes/microbiologia , Proteínas de Peixes/genética , Sistemas de Secreção Tipo III/genética , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/metabolismo , Sequência de Bases , Linhagem Celular , Edwardsiella tarda/genética , Doenças dos Peixes/patologia , Proteínas de Peixes/metabolismo , Peixes , Regulação Bacteriana da Expressão Gênica , Células HeLa , Humanos , Camundongos , Transporte Proteico , Análise de Sequência de DNA , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
11.
Fish Shellfish Immunol ; 49: 34-44, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26702559

RESUMO

GRIM-19 (gene associated with retinoid-interferon-induced mortality 19), a novel cell death regulatory gene, plays important roles in cell apoptosis, mitochondrial respiratory chain and immune response. It has been reported to interact physically with STAT3 and inhibit STAT3-dependent signal transduction. In this study, a new GRIM-19 gene, which is a 789-bp gene encoding a 149 amino acids protein, is identified and characterized from Litopenaeus vannamei. The tissue distribution patterns showed that LvGRIM-19 was widely expressed in all examined tissues, with the highest expression in muscle. Quantitative real-time PCR revealed that LvGRIM-19 was down-regulated in hepatopancreas after infection with the Vibrio alginolyticus. Knockdown of LvGRIM-19 by RNA interference resulted in a lower mortality of L. vannamei under V. alginolyticus infection, as well as an enhancement in the protein expression of STAT gene and JAK gene. V. alginolyticus infection caused an increase apoptotic cell ratio and ROS production of L. vannamei, while LvGRIM-19 silenced shrimps showed significantly lower than GFP group. Our results suggest that the GRIM-19 plays a vital role in shrimps' responses to V. alginolyticus. Interferenced LvGRIM-19 treatment during V. alginolyticus infection could increase 12 h survival rate, which might indicated that LvGRIM-19 is closely related to death of shrimps.


Assuntos
Proteínas de Artrópodes/genética , Imunidade Inata , NADH NADPH Oxirredutases/genética , Penaeidae/imunologia , Penaeidae/microbiologia , Animais , Proteínas de Artrópodes/metabolismo , Regulação para Baixo , Hepatopâncreas/metabolismo , Janus Quinases/genética , Janus Quinases/metabolismo , Dados de Sequência Molecular , NADH NADPH Oxirredutases/metabolismo , Penaeidae/genética , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Transcrição STAT/genética , Fatores de Transcrição STAT/metabolismo , Análise de Sequência de DNA
12.
Fish Shellfish Immunol ; 58: 686-700, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27725262

RESUMO

PTEN is a key tumor suppressor gene that can play a regulatory role in the cellular proliferation, survival and apoptosis. In this study, the full-length PTEN (EcPTEN) was obtained, containing a 5'UTR of 745 bp, an ORF of 1269 bp and a 3'UTR of 106 bp. The EcPTEN gene encoded a polypeptide of 422 amino acids with an estimated molecular mass of 49.14 KDa and a predicted isoelectric point (pI) of 6.34. The deduced amino acid sequence analysis showed that EcPTEN comprised the conserved residues and the characteristic domains known to the critical functionality of PTEN. qRT-PCR analysis revealed that EcPTEN mRNA was broadly expressed in all the examined tissues, while the highest expression level was observed in liver, followed by the expression in blood, kidney, spleen, heart, gill, muscle and intestine. The groupers challenged with Vibrio alginolyticus showed a sharp increase of EcPTEN mRNA expression in immune tissues. In addition, western blotting analysis confirmed that the up-regulation of EcPTEN protein expression was steadily induced in liver. Subcellular localization analysis indicated that EcPTEN was localized in both nucleus and cytoplasm. Overexpression of EcPTEN can activate the apoptotic cascade and abrogate NF-kB, AP-1, Stat3 and Myc promoter activity in Hela cells. These results indicated that EcPTEN harboring highly-conserved domains with a close sequence similarity to those of PTP superfamily may disrupt the mammalian signalings and play a regulatory role in the apoptotic process.


Assuntos
Bass , Doenças dos Peixes/genética , Proteínas de Peixes/genética , Regulação da Expressão Gênica , Lipopolissacarídeos/farmacologia , PTEN Fosfo-Hidrolase/genética , Vibrioses/veterinária , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , DNA Complementar/metabolismo , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Proteínas de Peixes/química , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , PTEN Fosfo-Hidrolase/química , PTEN Fosfo-Hidrolase/metabolismo , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência/veterinária , Distribuição Tecidual , Vibrioses/genética , Vibrioses/imunologia , Vibrioses/microbiologia , Vibrio alginolyticus/fisiologia
13.
Protein Expr Purif ; 109: 23-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25637142

RESUMO

The α2-macroglobulin receptor (α2MR) is a major domain of complement component 3b, which may play an important role in regulating the downstream complement system in teleosts. In order to characterize the domain thoroughly larger than currently available quantities are required. Thus, in this study the Epinephelus coioides α2MR (Ec-α2MR) was expressed and secreted by the methylotrophic yeast Pichia pastoris with variations in pH and induction time to identify optimal production conditions. At pH 5.5 with 48h induction 13mg of Ec-α2MR (ca. 90% purity) was obtained from 500ml of culture. The Ec-α2MR protein product was validated by MALDI-TOF MS sequence analysis, and both Western blotting and ELISAs demonstrated that it possessed the expected activity, binding to C3b or C3b homolog antibodies, and thus can be used for future studies of the interactions and functions of complement proteins in teleosts.


Assuntos
Bass/genética , Complemento C3b/genética , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Pichia/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos/metabolismo , Western Blotting , Precipitação Química , Clonagem Molecular , Complemento C3b/química , Complemento C3b/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Concentração de Íons de Hidrogênio , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/química , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/isolamento & purificação , Dados de Sequência Molecular , Proteínas Recombinantes/metabolismo , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Transformação Genética
14.
Fish Shellfish Immunol ; 44(1): 180-6, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25703712

RESUMO

DJ-1 was first identified as an oncogene that transformed mouse NIH3T3 cells in cooperation with activated Ras. It has since exhibited a variety of functions in a range of organisms. In this study, the DJ-1 gene in Litopenaeus vannamei (LvDJ-1) was identified and characterized. A recombinant protein LvDJ-1 was produced in Pichia pastoris. LvDJ-1 expression in vivo was knocked down by dsRNA-mediated RNA interference (RNAi), which led to significantly decreased levels of LvDJ-1 mRNA and protein. When the L. vannamei were challenged with RNAi and Vibrio alginolyticus, the transcription and expression of copper zinc superoxide dismutase (LvCZSOD) in the hepatopancreas were dramatically lower in shrimp with knocked down LvDJ-1 than in controls. Transcription and expression of P53 (LvP53) were significantly higher in shrimp lacking LvDJ-1 than in controls. Hepatopancreas samples were analyzed using real time polymerase chain reaction and Western blot. Moreover, blood samples from the shrimp, assessed with flow cytometry, showed significant increases in respiratory burst and apoptosis in those lacking LvDJ-1 compared to the controls. Cumulative mortality in the shrimp lacking LvDJ-1 was significantly different from that in the control group after challenge with V. alginolyticus. Altogether, the results prove that LvDJ-1 regulates apoptosis and antioxidant activity, and that these functions play an important role in L. vannamei resistance against V. alginolyticus.


Assuntos
Proteínas de Artrópodes/genética , Resistência à Doença/genética , Proteínas Oncogênicas/genética , Penaeidae/genética , Penaeidae/microbiologia , Vibrio alginolyticus/fisiologia , Sequência de Aminoácidos , Animais , Apoptose , Proteínas de Artrópodes/metabolismo , Sequência de Bases , Contagem de Células , Clonagem Molecular , Hemócitos/citologia , Hepatopâncreas/metabolismo , Dados de Sequência Molecular , Proteínas Oncogênicas/metabolismo , Penaeidae/fisiologia , Interferência de RNA , Explosão Respiratória , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
15.
Fish Shellfish Immunol ; 45(2): 346-56, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25917969

RESUMO

The effects of Ec-α2MR (Epinephelus coiodes-α2-macroglobulin receptor) on growth performance, enzymatic activity, respiratory burst, MDA level, total antioxidant capacity, DPPH radical scavenging percentage and immune-related gene expressions of the juvenile orange-spotted grouper were evaluated. The commercial diet supplemented with α2MR additive was used to feed the orange-spotted grouper for six weeks. Although a slight increase was observed in the specific growth rate, survival rate and weight gain, no significance was observed among different group. After the feeding trial, the groupers were exposed to cold stress. Respiratory burst activity and MDA level decreased significantly in α2MR additive group by comparing with the control and additive control group, while a sharp increase of ACP activity, ALP activity, total antioxidant capacity and DPPH radial scavenging percentage was observed in α2MR additive group. qRT-PCR analyses confirmed that the up-regulated mRNA expressions of C3, TNF1, TNF2, IL-6, CTL, LysC, SOD1 and SOD2 were observed in α2MR additive group at 20 °C. These results showed that α2MR additive may moderate the immune response in grouper following cold shock challenge.


Assuntos
Bass/fisiologia , Resposta ao Choque Frio , Imunidade Inata , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Bass/crescimento & desenvolvimento , Bass/imunologia , Dieta/veterinária , Suplementos Nutricionais/análise , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Longevidade/efeitos dos fármacos , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/administração & dosagem , Distribuição Aleatória
16.
Ecotoxicology ; 24(7-8): 1775-87, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25956977

RESUMO

Vibrio alginolyticus containing the highly toxic extracellular product is one of the most serious threats to grouper survival and its minimum lethal dose is approximately 500 CFU/g fish body weight in grouper. To study the toxic effects of V. alginolyticus on the immune system in teleost, Calmodulin (CaM), an important molecular indicator gene, was cloned from the orange-spotted grouper (Epinephelus coioides). The full-length Ec-CaM consisted of a 5'-UTR of 103 bp, an ORF of 450 bp and a 3'-UTR of 104 bp. The Ec-CaM gene encoded a protein of 149 amino acids with an estimated molecular mass of 16.4 kDa and a predicted isoelectric point of 3.93. The deduced amino acid sequence showed that Ec-CaM contained four highly conserved EF-hand domains known to be critical for the function of CaM. Ec-CaM was widely expressed and the highest expression level was observed in liver. Following V. alginolyticus challenge, a sharp increase level of respiratory burst activity and apoptosis ratio were observed. Further analyses of CaM expression and p53 expression in liver, kidney and spleen by qRT-PCR demonstrated that the up-regulated expression of CaM and p53 were observed in the vibrio challenge group. Western blotting analysis confirmed that the Ec-CaM protein was strongly induced in liver at 12 h post-injection, while a sharp increase of p53 protein expression was observed at 24 h post-injection. These results showed CaM expression serving as a potential molecular indicator may help to assess the toxicological effects of V. alginolyticus on the ROS generation and apoptotic process in grouper.


Assuntos
Bass , Calmodulina/genética , Doenças dos Peixes/genética , Proteínas de Peixes/genética , Regulação da Expressão Gênica , Vibrioses/veterinária , Vibrio alginolyticus/fisiologia , Sequência de Aminoácidos , Animais , Apoptose , Sequência de Bases , Calmodulina/metabolismo , Clonagem Molecular , DNA Complementar/genética , DNA Complementar/metabolismo , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Proteínas de Peixes/metabolismo , Perfilação da Expressão Gênica , Dados de Sequência Molecular , Especificidade de Órgãos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Explosão Respiratória , Alinhamento de Sequência , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Vibrioses/genética , Vibrioses/imunologia , Vibrioses/microbiologia
17.
Ecotoxicology ; 24(7-8): 1765-74, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25952560

RESUMO

With the destruction of the ecological environment, shrimp cultivation in China has been seriously affected by outbreaks of infectious diseases. Rab, which belong to small GTPase Ras superfamily, can regulate multiple steps in eukaryotic vesicle trafficking including vesicle budding, vesicle tethering, and membrane fusion. Knowledge of Rab in shrimp is essential to understanding regulation and detoxification mechanisms of environmental stress. In this study, we analyzed the functions of Rab from the Pacific white shrimp, Litopenaeus vannamei. Full-length cDNA of Rab was obtained, which was 751 bp long, with open reading frame encoding 206 amino acids. In this study, for the first time, the gene expression of Rab of L. vannamei was analyzed by quantitative real-time PCR after exposure to five kinds of environmental stresses (bacteria, pH, Cd, salinity and low temperature). The results demonstrate that Rab is sensitive and involved in bacteria, pH, and Cd stress responses and Rab is more sensitive to bacteria than other stresses. Therefore we infer that Rab may have relationship with the anti-stress mechanism induced by environment stress in shrimp and Rab could be used as critical biomarkers for environmental quality assessment.


Assuntos
Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Penaeidae/genética , Penaeidae/metabolismo , Estresse Fisiológico/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , DNA Complementar/metabolismo , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Técnicas de Hibridização Subtrativa , Proteínas ras/genética , Proteínas ras/metabolismo
18.
Fish Physiol Biochem ; 41(5): 1345-58, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26122279

RESUMO

The effects of Dissostichus mawsoni-Calmodulin (Dm-CaM) on growth performance, enzyme activities, respiratory burst, MDA level and immune-related gene expressions of the orange-spotted grouper (Epinephelus coioides) exposed to the acute low temperature stress were evaluated. The commercial diet supplemented with Dm-CaM protein was fed to the groupers for 6 weeks. No significant difference was observed in the specific growth rates, weight gains and survivals. After the feeding trial, the groupers were exposed to acute low temperature challenge. The groupers fed with Dm-CaM additive diet showed a significant decrease in the respiratory burst activity, while the blood cell number increased significantly at 25 °C by comparing with the control and additive control group. The enzymatic activity of SOD, ACP and ALP increased significantly in Dm-CaM additive group, while MDA level maintained stable with the lowest value. qRT-PCR analysis indicated that the up-regulated transcript expressions of CaM, C3, SOD2, LysC and HSPA4 were observed in Dm-CaM additive group. These results indicated that Dm-CaM additive diet may regulate the grouper immune response to the acute low temperature challenge.


Assuntos
Ração Animal/análise , Calmodulina/farmacologia , Temperatura Baixa , Proteínas de Peixes/metabolismo , Perciformes/crescimento & desenvolvimento , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária
19.
Fish Shellfish Immunol ; 36(2): 475-84, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24412164

RESUMO

The effect of Ec-FABP10 (Epinephelus coiodes-FABP10) on growth performance, enzyme activity, respiratory burst, MDA level, ATP content, immune-related gene expression of juvenile orange-spotted grouper (E. coioides). The commercial diet supplemented with FABP10 protein was feed to orange-spotted grouper for six weeks. No significant difference was observed in the specific growth rates, while the survival rate in the FABP10 additive group was significantly higher. After the feeding trial, the groupers were exposed to acute low temperature challenge. The decreased level of respiratory burst activity was observed in the FABP10 additive group after the exposure to the acute low temperature stress, while the blood cell count increased significantly at 15 °C and a significant increase of ATP content was observed at 10 °C. Higher enzymatic activities of CAT and SOD were observed at 20 °C and 15 °C, respectively. Meanwhile, the lower level of MDA was observed after the exposure to acute low temperature challenge by comparing with the controls. Further transcript expression analyses of FABP10, SOD2, GPX4, HSPA4 and LIPC in liver by quantitative real-time PCR demonstrated that the up-regulated transcript expression of FABP10, SOD2, HSPA4 and LIPC was observed in FABP10 additive group at 15 °C, while the transcript expression of GPX4 increased significantly at 20 °C. Western blotting analysis confirmed that FABP10 protein expression strongly increased at 15 ± 0.5 °C in FABP10 additive group. These results showed that FABP10 additive diet could moderate the metabolic and immune abilities mainly via ROS pathway in the orange-spotted grouper.


Assuntos
Bass/fisiologia , Temperatura Baixa , Proteínas de Ligação a Ácido Graxo/genética , Proteínas de Ligação a Ácido Graxo/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica , Ração Animal/análise , Animais , Bass/crescimento & desenvolvimento , Bass/imunologia , Dieta/veterinária , Suplementos Nutricionais/análise , Proteínas de Ligação a Ácido Graxo/administração & dosagem , Proteínas de Peixes/administração & dosagem , Pesqueiros , Perfilação da Expressão Gênica/veterinária , Testes Hematológicos/veterinária , Imunidade Inata , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Estresse Fisiológico
20.
Small Methods ; : e2400224, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38697931

RESUMO

The pursuit of high energy densities propels the design of next-generation nickel-based layered oxide cathodes. The utilization of low-cobalt, ultrahigh-nickel layered oxide cathodes, and the extension of operating voltages promise enhanced energy density. However, stability and safety face challenges associated with nickel content, including structural degradation, lattice oxygen evolution, and thermal instability. In this study, a promising strategy of Al and Nb dual-bulk-doping is presented in high-Ni cathode materials of LiNi0.96Co0.04O2 (NC) to stabilize the bulk structure, suppress oxygen release, and attain superior electrochemical performance at high voltages. The introduction of Al and Nb effectively raises the migration energy of Ni2+ into Li sites and stabilizes lattice oxygen through strengthened Al─O and Nb─O bonds. Furthermore, the substitution of high-valence Nb ions reduces the charge depletion of lattice oxygen and induces an ordered microstructure. The Al and Nb dual-bulk-doping strategy mitigates strain and stress associated with the H2↔H3 phase transition, reducing the generation and propagation of microcracks. The resulting Li(Ni0.96Co0.04)0.985Al0.01Nb0.005O2 (NCAN) cathode exhibits superior cycling stability, with a capacity retention of 77.8% after 300 cycles, even when operating at a high-voltage of 4.4 V, outperforming the NC (48.5%). This work provides a promising perspective for developing high-voltage and high-Ni cathode materials.

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