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1.
Chemosphere ; 239: 124668, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31494325

RESUMO

Nitrite is one of major environmental pollutants that can impact immunological parameters in aquatic organisms. In the present study, we investigated the effects of nitrite exposure on oxidative stress, DNA damage and apoptosis in mud crab (Scylla paramamosain). Mud crab were exposed to 0, 5, 10 and 15 mg L-1 nitrite for 72 h. These data showed that acid phosphatase (ACP) and alkaline phosphatase (ALP) activity significantly decreased in treatments with various concentrations of nitrite (5, 10 and 15 mg L-1) after 24 and 48 h, while the levels of nitric oxide (NO) significantly increased in these treatments. Nitrite exposure could suppress superoxide dismutase (SOD) and catalase (CAT) activity, and increase the formation of malondialdehyde (MDA) after 48 and 72 h of exposure. In addition, nitrite exposure decreased total haemocyte counts after 48 and 72 h of exposure. Cytological damage, DNA damage and apoptosis was observed obviously at 72 h after nitrite exposure. Moreover, nitrite exposure significantly induced the mRNA levels of phosphorylated Jun N-terminal kinases (JNK), and eventually activated p53 signaling and caspase-3. These results indicated that nitrite exposure could induce oxidative stress, which further caused DNA damage and apoptosis in mud crab. Our results will be helpful to understand the mechanism of nitrite toxicity on crustaceans.


Assuntos
Apoptose/efeitos dos fármacos , Braquiúros/efeitos dos fármacos , Dano ao DNA/genética , Nitritos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Fosfatase Ácida/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Braquiúros/genética , Catalase/metabolismo , Hemócitos , Malondialdeído/metabolismo , Óxido Nítrico/metabolismo , Transdução de Sinais , Superóxido Dismutase/metabolismo
2.
J Agric Food Chem ; 67(46): 12918-12926, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31668066

RESUMO

The triosephosphate isomerase (TIM), Scy p 8, is a crab allergen and shows cross-reactivity in the shellfish. Here, recombinant Scy p 8 was expressed, and its crystal structure was determined at a resolution of 1.8 Å. The three-dimensional structure of Scy p 8 is primarily composed of a (ß/α)8-barrel motif prototype. Additionally, Scy p 8 showed cross-reactivity with high sequential and secondary structural identity among TIMs from shellfish species. The site-directed mutagenesis of critical amino acids of conformational epitopes was carried out, and the mutants of Trp 168 and Lys 237 to Ala reduced immunoglobulin E (IgE)-binding activity by approximately 30%, compared with wild-type TIM in an inhibition ELISA; however, it still induced basophil activation despite the interpatient variability between patients. These results can help to provide an accurate template for the analysis of the IgE binding and establish meaningful relationships between structure and allergenicity.


Assuntos
Braquiúros/enzimologia , Epitopos/química , Triose-Fosfato Isomerase/imunologia , Sequência de Aminoácidos , Animais , Braquiúros/química , Braquiúros/genética , Braquiúros/imunologia , Reações Cruzadas , Cristalização , Epitopos/genética , Epitopos/imunologia , Humanos , Imunoglobulina E/imunologia , Conformação Molecular , Conformação Proteica , Alinhamento de Sequência , Frutos do Mar/análise , Hipersensibilidade a Frutos do Mar/imunologia , Triose-Fosfato Isomerase/química , Triose-Fosfato Isomerase/genética
3.
Anim Reprod Sci ; 208: 106122, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31405473

RESUMO

The vitellogenesis-inhibiting hormone (VIH), also known as gonad-inhibiting hormone, is a neuropeptide hormone in crustaceans that belongs to the crustacean hyperglycemic hormone (CHH)-family peptide. There is regulation vitellogenesis by VIH during gonad maturation in crustaceans. A full-length Scylla olivacea VIH (Scyol-VIH) was identified through reverse transcription polymerase chain reaction and rapid amplification of cDNA ends. The open reading frame consists of 378 nucleotides, which encodes a 126-amino acid precursor protein, including a 22-residue signal peptide and a 103-amino acid mature peptide in which 6 highly conserved cysteine residues are present. There was expression of the Scyol-VIH gene in immature female Scylla olivacea in the eyestalk, brain and ventral nerve cord. The Scyol-VIH gene expression was localized to the eyestalk X-organ, brain neuronal clusters 6 and 11, and in multiple neuronal clusters of the ventral nerve cord. The relative abundance of Scyol-VIH mRNA transcript in the eyestalk was relatively greater in immature stage females, then decreased as ovarian maturation progressed. Furthermore, eyestalk Scyol-VIH increased after dopamine (5 µg/g BW) injection. The present research provides fundamental information about Scyol-VIH and its potential effect in controlling reproduction.


Assuntos
Braquiúros/fisiologia , Dopamina/farmacologia , Hormônios de Invertebrado/metabolismo , Ovário/crescimento & desenvolvimento , RNA Mensageiro/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Braquiúros/genética , Clonagem Molecular , Dopamina/administração & dosagem , Dopaminérgicos/farmacologia , Antagonistas de Dopamina/administração & dosagem , Antagonistas de Dopamina/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônios de Invertebrado/genética , Ovário/metabolismo , Filogenia , RNA Mensageiro/genética , Serotonina/administração & dosagem , Serotonina/farmacologia , Serotoninérgicos/administração & dosagem , Serotoninérgicos/farmacologia , Maturidade Sexual , Espiperona/administração & dosagem , Espiperona/farmacologia , Fatores de Tempo
4.
Anim Reprod Sci ; 208: 106131, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31405476

RESUMO

Gonadal development usually involves alternative splicing of sex-related genes. Vasa, a highly conserved ATP-dependent RNA helicase present mainly in germ cells, has an important function in gonadal development. As an important sex-related gene, recent evidence indicates that different splice variants of vasa exist in many species. In this study, there was identification of two types of vasa splice variants in the Chinese mitten crab Eriocheir sinensis, termed Esvasa-l and Esvasa-s, respectively. Furthermore, splice variants of Esvasa-s were sub-divided into Esvasa-s1, Esvasa-s2, Esvasa-s3, Esvasa-s4, and Esvasa-s5, based on differing numbers of TGG repeats. Results from genomic structure analyses indicated that these forms are alternatively spliced transcripts from a single vasa gene. Results from tissue distribution assessments indicate the vasa splice variants were exclusively expressed in the gonads of male and female adult crabs. In situ hybridization results indicate Esvasa mRNA was mainly present in the cytoplasm of previtellogenic oocytes. As oocyte size increased, relative abundance of Esvasa mRNA decreased and became distributed near the cellular membrane. The Esvasa mRNA was not detectable in mature oocytes. In testis, Esvasa mRNA was detected in spermatids and spermatozoa, but not in spermatogonia and spermatocytes. Notably, results from qPCR analysis of Esvasa-l and Esvasa-s indicate there are different relative proportions during gametogenesis, implying that splice variants of the Esvasa gene may have different biological functions during crab gonadal development.


Assuntos
Processamento Alternativo , Braquiúros/genética , RNA Helicases DEAD-box/metabolismo , Gônadas/crescimento & desenvolvimento , RNA Mensageiro/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , RNA Helicases DEAD-box/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Regulação Enzimológica da Expressão Gênica/fisiologia , RNA Mensageiro/genética , Maturidade Sexual
5.
J Agric Food Chem ; 67(37): 10458-10469, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31469568

RESUMO

Mud crab (Scylla paramamosain) is a commonly consumed seafood as a result of its high nutritional value; however, it is associated with food allergy. The current understanding of crab allergens remains insufficient. In the present study, an 18 kDa protein was purified from crab muscle and confirmed to be myosin light chain 1 (MLC1) by matrix-assisted laser desorption/ionization-tandem time-of-flight mass spectrometry. Total RNA was isolated and amplified to obtain a MLC1 open reading frame of 462 bp, encoding 154 amino acids. A structural analysis revealed that recombinant MLC1 (rMLC1) expressed in Escherichia coli contained α-helix and random coil. Moreover, rMLC1 displayed strong immunoactivity by dot blot and a basophil activation test. Furthermore, seven allergenic epitopes of MLC1 were predicted, and five critical epitope regions were identified by an inhibition enzyme-linked immunosorbent assay and human mast cell degranulation assay. This comprehensive research of an allergen helps to conduct component-resolved diagnoses and immunotherapies related to crab allergies.


Assuntos
Alérgenos/imunologia , Proteínas de Artrópodes/imunologia , Braquiúros/genética , Clonagem Molecular , Epitopos/imunologia , Cadeias Leves de Miosina/imunologia , Alérgenos/química , Alérgenos/genética , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Braquiúros/química , Braquiúros/imunologia , Degranulação Celular , Epitopos/química , Epitopos/genética , Humanos , Mastócitos/imunologia , Cadeias Leves de Miosina/química , Cadeias Leves de Miosina/genética , Fases de Leitura Aberta , Alinhamento de Sequência
6.
Fish Shellfish Immunol ; 93: 251-257, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31319207

RESUMO

C-type lectins (CTLs) have characteristic carbohydrate recognition domains (CRDs) and play important roles in the immune system. In the present study, a new CTL, SpCTL5, was identified from the hepatopancreas of the mud crab Scylla paramamosain. The open reading frame of SpCTL5 comprised 762 bp, encoding a polypeptide of 253 amino acids with a putative signaling peptide of 20 amino acids. The predicted SpCTL5 protein contained a single CRD. SpCTL5 transcripts were distributed in all examined tissues, with the highest level being detected in the hepatopancreas. Upon challenging with Vibrio alginolyticus, the mRNA levels of SpCTL5 in the hepatopancreas were up-regulated. The recombinant protein of SpCTL5 could agglutinate three Gram-positive bacteria and three Gram-negative bacteria in the presence of Ca2+. Furthermore, hemagglutination analysis showed that the recombinant protein of SpCTL5 can agglutinate rabbit erythrocytes. This study indicated that SpCTL5 acts as a pattern recognition receptor for the innate immune response which protects S. paramamosain from bacterial infection. Moreover, these findings also provide information to further our understanding of the innate immunology of invertebrates.


Assuntos
Braquiúros/genética , Braquiúros/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Aglutinação , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Clonagem Molecular , Perfilação da Expressão Gênica , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/fisiologia , Lectinas Tipo C/química , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Alinhamento de Sequência
7.
Ecotoxicol Environ Saf ; 181: 301-307, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31202929

RESUMO

Metallothioneins (MTs) are a family of low molecular weight, cysteine-rich, metal-binding proteins, which play important roles in metal homeostasis and heavy metal detoxification. In our previous study, a novel full length MT cDNA was successfully cloned from the freshwater crab (Sinopotamon henanense). In the present study, tandem repeats of two and three copies of the crab MT gene were integrated by overlap extension PCR (SOE-PCR) and expressed in Escherichia coli. The SUMO fusion expression system was adopted to increase the stability and solubility of the recombinant MT proteins. The recombinant proteins were purified and their metal-binding abilities were further analyzed by the ultraviolet absorption spectral scan. Furthermore, the metal tolerance and bioaccumulation of E. coli cells expressing oligomeric MTs were determined. Results showed that the recombinant plasmids pET28a-SUMO-2MT and pET28a-SUMO-3MT were successfully constructed. SDS-PAGE analysis showed that the SUMO-2MT and SUMO-3MT were expressed mainly in the soluble forms. Oligomeric MTs expression significantly enhanced Cu, Cd or Zn tolerance and accumulation in E. coli in the order: SUMO-3MT˃SUMO-2MT˃SUMO-MT˃control. Cells harboring pET28a-SUMO -3MT exhibited the highest Cu, Cd or Zn bioaccumulation at 5.8-fold, 3.1-fold or 6.7-fold higher than that of the control cells. Our research could lay a foundation for large-scale preparation of MTs and provide a scientific basis for bioremediation of heavy metal pollution by oligomeric MTs.


Assuntos
Escherichia coli/genética , Metalotioneína/genética , Metais Pesados/metabolismo , Animais , Braquiúros/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Metalotioneína/metabolismo , Metais Pesados/toxicidade , Proteínas Recombinantes de Fusão/metabolismo
8.
Genes Genomics ; 41(8): 961-971, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31127502

RESUMO

BACKGROUND: Low salinity is one of the main factors limiting the distribution and survival of marine species. As a euryhaline species, the swimming crab (Portunus trituberculatus) is adaptive to relatively low salinity. However, the mechanisms underlying salinity stress responses in P. trituberculatus is not very clear. OBJECTIVES: The primary objective of this study was to describe the salinity adaptation mechanism in P. trituberculatus. METHODS: The crabs were exposed to low salinity stress, and gill tissue was sampled at 0, 12, 36, 48 and 72 h and subjected to high throughput sequencing. Subsequently, we tested the accuracy and quality of the sequencing results, and then carried out GO and KEGG bioinformatics on the differentially expressed genes (DEG). RESULTS: Each sample yielded more than 1.1 Gb of clean data and 23 million clean reads. The process was divided into early (0-12 h), middle (12-48 h), and late phase (48-72 h). A total of 1971 (1373 up-regulated, 598 down-regulated), 1212 (364 up-regulated, 848 down-regulated), and 555 (187 up-regulated, 368 down-regulated) DEGs with annotations were identified during the three stages, respectively. DEGs were mainly associated with lipid metabolism energy metabolism, and signal transduction from the three stages, respectively. CONCLUSION: A substantial number of genes were modified by salinity stress, along with a few important salinity acclimation pathways. This work provides valuable information on the salinity adaptation mechanism in P. trituberculatus. In addition, the comprehensive transcript sequences reported in this study provide a rich resource for identification of novel genes in this and other crab species.


Assuntos
Braquiúros/genética , Tolerância ao Sal , Transcriptoma , Animais , Braquiúros/metabolismo , Brânquias/metabolismo , Metabolismo dos Lipídeos
9.
Fish Shellfish Immunol ; 90: 264-273, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31054356

RESUMO

We investigated the effects of icariin (ICA) on growth performance, antioxidant capacity and non-specific immunity in Chinese mitten crab (Eriocheir sinensis). A total of 200 healthy crabs (average weight: 33.58 ±â€¯0.05 g) were randomly assigned to four treatments with five replicates, each with ten individuals per pool. There were four dietary treatments: the control group (fed with the basal diet), the ICA 50 group, the ICA100 group, and the ICA 200 group (fed with the basal diet supplemented with 50, 100, and 200 mg/kg ICA, respectively). These diets were provided for 8 weeks. Results indicated that ICA100 crabs had higher weight gain (WG), specific growth rate (SGR) and survival rate (SR) than the controls. Protein carbonyl content (PCC) and malondialdehyde (MDA) concentrations in the haemolymph and hepatopancreas of ICA100 crabs were significantly lower than in the control group, while the superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were significantly higher. The activities of PO, LZM, ACP and AKP were significantly enhanced with ICA supplementation at 50 and 100 mg/kg, yet decreased subsequently at 200 mg/kg. Furthermore, supplementation of 100 mg/kg ICA up-regulated the mRNA expression of prophenoloxidase (proPO), catalase (CAT), mitochondrial manganese superoxide dismutase (mtMnSOD), thioredoxin-1 (Trx1) and peroxiredoxin 6 (Prx6), while the mRNA expression of toll like receptors (TLRs), NF-κB-like transcription factor Relish and lipopolysaccharide-induced TNF-α factor (LITAF) were down-regulated in the hepatopancreas (P < 0.05). These findings indicate that dietary ICA supplementation at an optimum dose of 100 mg/kg may be effective in improving growth performance, antioxidant capability and non-specific immunity of Chinese mitten crab.


Assuntos
Adjuvantes Imunológicos/metabolismo , Braquiúros/imunologia , Flavonoides/metabolismo , Imunidade Inata/efeitos dos fármacos , Adjuvantes Imunológicos/administração & dosagem , Ração Animal/análise , Animais , Antioxidantes , Braquiúros/genética , Braquiúros/crescimento & desenvolvimento , Braquiúros/metabolismo , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Flavonoides/administração & dosagem , Distribuição Aleatória
10.
Zoo Biol ; 38(4): 343-354, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31056807

RESUMO

Zoos increasingly transform their exhibitions from traditional one-species enclosures to more natural exhibits, that is, environments that capture part of an ecosystem including a selection of animals and plants that occur there. Thus, enhancing the experience of its human visitors while also allowing its residents to possibly show more natural behavior. In 2017 Royal Burger's Zoo (Arnhem, The Netherlands) created and opened a mangrove-like environment containing fiddler crabs. Fiddler crabs display a broad range of behaviors, and this research examines which wild-type behavior and behavioral patterns can be observed on a seminatural mudflat. The behavior shown by Uca rapax and Uca tangeri on the mudflat was counted each hour between 07:00 and 17:00. An asymmetric tidal regime was present in the enclosure including two high water periods. Various known fiddler crab behaviors, including waving and combat, were observed but no copulation. A clear pattern in exposed crabs on the mudflat was found, with low numbers visible in the early morning and the highest numbers present in the early afternoon, while number of visitors did not have a significant effect on this pattern. Interestingly, the highest abundances were not observed around the ebbing tide (07:00-09:00), as observed in the wild, but somewhat later, possibly due to the asymmetric tidal scheme or the interaction of tidal and daily rhythms. This study shows that in captivity, fiddler crabs indeed show a range of natural behaviors which is linked to the tidal and possibly daily rhythm as well.


Assuntos
Comportamento Animal , Braquiúros/genética , Braquiúros/fisiologia , Abrigo para Animais , Animais , Animais de Zoológico , Especificidade da Espécie
11.
Gene ; 710: 1-8, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31078655

RESUMO

Investigation of sex determination system in Eriocheir sinensis is important because of sex-dimorphism in its growth traits. However, little information about the sex-related genes in embryonic development stages were exposed. To obtain more information of sex determination in Chinese mitten crab, we performed the transcriptome analysis in embryonic development stage (fertilized egg stage, cleavage stage, blastula stage, gastrula stage and heartbeat stage) of Chinese mitten crab using nextgeneration sequencing technology. Thirty-one of 32,088 annotated unigenes were identified as sex-related genes including 16 genes involved in primary sex determination in model organisms and 8 genes of SOX family and 7 genes of DMRT gene family. Heatmap based on the RPKM value in five embryonic development stages indicated that these genes were clustered into two branches. Analysis of the differentially expressed 12 genes, including 3 genes of SOX family, 3 genes of DMRT gene family and 6 genes involved in primary sex determination in model organisms, showed significantly difference between the first three periods (fertilized egg stage-cleavage stage-blastula stage) and the last two periods (gastrula stage-heartbeat stage) and all 12 genes were up-regulated after blastula stage. In conclusion, we inferred that sex determination might be initiated after blastula stage in E. sinensis. Transcriptome analysis from embryonic development stage could provide a background information for further investigation in sex determination of Eriocheir sinensis.


Assuntos
Proteínas de Artrópodes/genética , Braquiúros/embriologia , Perfilação da Expressão Gênica/métodos , Caracteres Sexuais , Animais , Braquiúros/genética , Desenvolvimento Embrionário , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Família Multigênica , Análise de Sequência de RNA
12.
Artigo em Inglês | MEDLINE | ID: mdl-31075503

RESUMO

The functions of Wnt signalling in crab limb regeneration are poorly understood. Herein, we isolated and characterised the full-length cDNA of WNT4 from Portunus trituberculatus, designated PtWNT4. The 4831 bp cDNA encodes 323 amino acid polypeptide. Protein structure prediction showed that PtWNT4 has a conserved WNT domain. The PtWNT4 gene was expressed in all regenerative limb stages, and was upregulated from stage I, with highest expression in stage III, and expression then declined in stages IV and V. Immunohistochemistry revealed strong localisation at loose connective tissue during limb regeneration, but PtWNT4 protein levels decreased upon formation of muscle fibers. Injection of WNT4 dsRNA into regenerative limbs significantly decreased PtWNT4 mRNA levels from 36 h to 5 days after injection, indicating successful gene silencing. RNA interference knockdown of PtWNT4 expression greatly retarded limb regeneration compared with the control group. Blastema emergence phenotype analysis revealed limb regeneration rates of 0, 31.5% and 40.5% for the dsWNT4 group at 36 h, 3 days and 5 days, respectively, compared with 29.95%, 83.0% and 92.5% for the saline-injected control groups (p <0.05). Expression analysis on the WNT4 using RNAi provide important information for understanding its functional mechanism during limb regeneration in P. trituberculatus. The results also contribute to our understanding of the role of Wnt signalling during limb regeneration in crustaceans.


Assuntos
Proteínas de Artrópodes/metabolismo , Braquiúros/metabolismo , Membro Posterior/fisiologia , Interferência de RNA , Regeneração/fisiologia , Proteína Wnt4/metabolismo , Animais , Proteínas de Artrópodes/genética , Braquiúros/genética , Proteína Wnt4/genética
13.
BMC Evol Biol ; 19(1): 105, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101005

RESUMO

BACKGROUND: The Pleistocene cyclic sea-level fluctuations are thought to have markedly affected the distribution and genetic architecture of Atlanto-Mediterranean biota. Despite the acknowledged key role played by these historical events in shaping population genetic structure of marine species, little is still known about the processes involved in shaping the spatial distribution of genetic variation within intertidal species. We intended in this study to reconstruct the phylogeography of a common and widely distributed coastal species across the East Atlantic and Mediterranean Sea (the warty crab Eriphia verrucosa), aiming to unravel potential microevolutionary processes likely involved in shaping its genetic polymorphism. For this purpose, a total of 155 specimens of E. verrucosa from 35 locations across the entire distribution range were analyzed by comparing a 453 basepairs region of the mitochondrial gene cytochrome oxidase subunit 1 (Cox1). RESULTS: Our results unveiled the prevalence of high genetic connectivity among East Atlantic and Mediterranean populations, with noticeable genetic distinctiveness of the peripheral population from the Azores. Spatio-temporal patterns of genetic diversification and demographic history allowed retrieving genetic imprints of late Pleistocene vicariant event across the Gibraltar Strait followed by subsequent postglacial expansion events for both the East Atlantic and Mediterranean regions. Integrative evidences from the outcomes of comparison of regional genetic diversification, as well as evolutionary and biogeographic histories reconstructions, support the existence of potential glacial refugia for E. verrucosa in the East Atlantic and western Mediterranean. Our results also revealed low levels of genetic variability along with recent demographic and spatial expansion events for eastern Mediterranean warty crabs, suggesting that the eastern areas within the distribution range of the species might have been recently colonized from putative glacial refugia. CONCLUSIONS: These findings provide new insights into the phylogeography and evolutionary history of a common but poorly studied Atlanto-Mediterranean decapod species. Specifically, they contribute to the understanding of the impact of historical processes on shaping contemporary population genetic structure and diversity in intertidal marine species.


Assuntos
Braquiúros/genética , Camada de Gelo , Filogenia , Filogeografia , Refúgio , Animais , Sequência de Bases , Teorema de Bayes , Complexo IV da Cadeia de Transporte de Elétrons/genética , Variação Genética , Gibraltar , Haplótipos/genética , Mar Mediterrâneo , Fatores de Tempo
14.
BMC Evol Biol ; 19(1): 92, 2019 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-30999853

RESUMO

BACKGROUND: Hyperdiverse mtDNA with more than 5% of variable synonymous nucleotide sites can lead to erroneous interpretations of population genetic differentiation patterns and parameters (φST, DEST). We illustrate this by using hyperdiverse mtDNA markers to infer population genetic differentiation and connectivity in Melarhaphe neritoides, a NE Atlantic (NEA) gastropod with a high dispersal potential. We also provide a recent literature example of how mtDNA hyperdiversity may have misguided the interpretation of genetic connectivity in the crab Opecarcinus hypostegus. RESULTS: mtDNA variation surveyed throughout the NEA showed that nearly all M. neritoides specimens had haplotypes private to populations, suggesting at first glance a lack of gene flow and thus a strong population genetic differentiation. Yet, the bush-like haplotype network, though visually misleading, showed no signs of phylogeographic or other haplotype structuring. Coalescent-based gene flow estimates were high throughout the NEA, irrespective of whether or not mtDNA hyperdiversity was reduced by removing hypervariable sites. CONCLUSIONS: Melarhaphe neritoides seems to be panmictic over the entire NEA, which is consistent with its long-lived pelagic larval stage. With hyperdiverse mtDNA, the apparent lack of shared haplotypes among populations does not necessarily reflect a lack of gene flow and/or population genetic differentiation by fixation of alternative haplotypes (DEST ≈ 1 does not a fortiori imply φST ≈ 1), but may be due to (1) a too low sampling effort to detect shared haplotypes and/or (2) a very high mutation rate that may conceal the signal of gene flow. Hyperdiverse mtDNA can be used to assess connectivity by coalescent-based methods. Yet, the combined use of φST and DEST can provide a reasonable inference of connectivity patterns from hyperdiverse mtDNA, too.


Assuntos
DNA Mitocondrial/genética , Genética Populacional , Haplótipos/genética , Polimorfismo Genético , Animais , Braquiúros/genética , Fluxo Gênico , Mitocôndrias/genética
15.
Gen Comp Endocrinol ; 280: 115-122, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31002828

RESUMO

Estradiol is an important sex steroid hormone that involved in regulation of animal lipid metabolism. However, the effect of estradiol on lipid metabolism in swimming crab (Portunus trituberculatus) is unclear. The present study investigated the effect of four concentrations of exogenous estradiol (0, 0.01, 0.1 and 1 µg g-1 crab weight) on the expression levels of lipid metabolism-related genes, lipid composition and histology of hepatopancreas in the P. trituberculatus. The results showed that the mRNA levels of carnitine palmitoyltransferase I and II (CPT-I and CPT-II) increased significantly at the low concentrations (0.01 µg g-1 and 0.1 µg g-1), while decreased significantly in the highest concentration (1 µg g-1). The mRNA levels of acyl-CoA oxidase (ACOX), fatty acid transport protein (FATP), fatty acid-binding protein (FABP), diacylglycerol acyltransferase 1 (DGAT1) and acetyl-CoA carboxylase (ACC) were significantly down-regulated. The transcripts of fatty acid synthase (FAS) and fatty acyl desaturase (FAD) decreased significantly only in 1 µg g-1 treatment. All estradiol treatments (0.01, 0.1 and 1 µg g-1) had significantly higher percentages of 20:4n6, 20:5n3 and 22:6n3, but lower percentages of total monounsaturated fatty acids and polar lipids than the control treatment (0 µg g-1). Histological observations indicated the size of B cell became larger under estradiol treatment. The results indicated that estradiol promoted lipid catabolism in the hepatopancreas of P. trituberculatus.


Assuntos
Braquiúros/metabolismo , Estradiol/farmacologia , Hepatopâncreas/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Natação , Animais , Peso Corporal/efeitos dos fármacos , Braquiúros/efeitos dos fármacos , Braquiúros/genética , Ácidos Graxos/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatopâncreas/citologia , Hepatopâncreas/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Oxirredução , RNA Mensageiro/genética
16.
Fish Shellfish Immunol ; 90: 80-90, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31022453

RESUMO

Transforming growth factor-ß-activating kinase 1 (TAK1) is essential for diverse important biological functions, such as innate immunity, development and cell survival. In the present study, the homologs of TAK1 and TAK1-binding protein 1 (TAB1) were identified and characterized from mud crab Scylla paramamosain for the first time. The full-length cDNAs of SpTAK1 and SpTAB1 were 2, 226 bp and 2, 433 bp with 1, 782 bp and 1, 533 bp open reading frame (ORF), respectively. The deduced SpTAK1 protein contained a conserved S_TKc (Serine/threonine protein kinases, catalytic) domain, and the putative SpTAB1 protein possessed a typical PP2Cc (Serine/threonine phosphatases, family 2C, catalytic) domain and a potential TAK1 docking motif. Real-time PCR analysis showed that SpTAK1 and SpTAB1 were highly expressed at early development stages, suggesting their participation in crab's development process. Moreover, the expression levels of SpTAK1 and SpTAB1 in hepatopancreas were positively stimulated after challenge with Vibro alginolyticus and Poly (I:C), implying the involvement of SpTAK1 and SpTAB1 in innate immune responses against both bacterial and viral infections. When SpTAK1 or SpTAB1 were silenced in vivo, the expression levels of two IMDNFκB signaling components (SpIKKß and SpRelish) and six antimicrobial peptide (AMP) genes (SpALF1-5 and SpCrustin) were significantly reduced, and the bacteria clearance capacity of crabs was also markedly impaired in SpTAK1 or SpTAB1 silenced crabs. Additionally, overexpression of SpTAK1 and SpTAB1 in HEK293T cells could markedly activate the mammalian NF-κB signaling. Collectively, our results suggested that TAK1 and TAB1 regulated crab's innate immunity via modulating the IMDNFκB signaling. These findings may provide new insights into the TAK1/TAB1-mediated signaling cascades in crustaceans and pave the way for a better understanding of crustacean innate immune system.


Assuntos
Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Braquiúros/genética , Braquiúros/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Perfilação da Expressão Gênica , MAP Quinase Quinase Quinases/química , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/imunologia , Filogenia , Alinhamento de Sequência , Transdução de Sinais/genética
17.
Ecotoxicol Environ Saf ; 179: 9-16, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31022654

RESUMO

Ammonia is a major aquatic environmental pollutants. However, the underlying molecular mechanism of ammonia-induced toxicity is not fully understood. In this study, we investigated the physiological response and molecular mechanism in mud crab (Scylla paramamosain) exposed to the acute total ammonia (30 mg L-1) for 48 h. The results shown that ammonia exposure induced oxidative stress, and subsequently led to cytological damage and DNA damage. Transcriptome analysis was applied to investigate the key genes and pathways involved in the responses to ammonia exposure. A total of 722 differentially expressed genes (DEGs) (526 up-regulated and 196 down-regulated) were identified. DEGs mainly involved in pathways including metabolism, cellular processes, signal transduction and immune functions. Additionally, transcriptome analysis revealed that ATM/p53-Caspase3 pathway involved in apoptosis induced by ammonia stress. These results provided a new insight into the mechanism of the potential toxic effects of ammonia on crustaceans.


Assuntos
Amônia/toxicidade , Braquiúros/efeitos dos fármacos , Dano ao DNA , Transcriptoma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Braquiúros/genética , Braquiúros/fisiologia , Perfilação da Expressão Gênica , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Transdução de Sinais
18.
PLoS One ; 14(4): e0215829, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31017948

RESUMO

To understand the origin, migration, and distribution of organisms across disjunct deep-sea vent habitats, previous studies have documented the population genetic structures of widely distributed fauna, such as gastropods, bivalves, barnacles, and squat lobsters. However, a limited number of investigations has been conducted in the Southwest Pacific Ocean, and many questions remain. In this study, we determined the population structure of the bythograeid crab Austinograea alayseae from three adjacent vent systems (Manus Basin, North Fiji Basin, and Tonga Arc) in the Southwest Pacific Ocean using the sequences of two mitochondrial genes (COI and 16S rDNA) and one nuclear gene (28S rDNA). Populations were divided into a Manus clade and a North Fiji-Tonga clade, with sequence divergence values in the middle of the barcoding gap for bythograeids. We inferred that hydrographic and/or physical barriers act on the gene flow of A. alayseae between the Manus and North Fiji basins. Austinograea alayseae individuals interact freely between the North Fiji Basin and the Lau Basin (Tonga Arc). Although further studies of genetic differentiation over a geological time scale, life-history attributes, and genome-based population genetics are needed to improve our understanding of the evolutionary history of A. alayseae, our results contribute to elucidating the phylogeny, evolution, and biogeography of bythograeids.


Assuntos
Braquiúros/genética , Genética Populacional , Fontes Hidrotermais , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Geografia , Haplótipos/genética , Oceano Pacífico , Filogenia , Especificidade da Espécie
19.
Fish Shellfish Immunol ; 89: 574-585, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30995541

RESUMO

Alpha-2 macroglobulin (A2M) is a ubiquitous protease inhibitor involved in the innate host defense system. Herein, two distinct A2M genes (designated as PtA2M-1 and PtA2M-2, respectively) were isolated from the swimming crab Portunus trituberculatus. PtA2M-1 and PtA2M-2 encoded proteins with 1541 or 1516 amino acids, respectively, containing the typically functional domains of A2M. Unlike highly expressed in hemocytes of most arthropods, PtA2M-1 and PtA2M-2 were predominantly detected in gill, eyestalk and digestive tracks. During the embryonic stages, PtA2Ms were found to be expressed most highly in fertilized eggs, suggesting their maternal origin. After challenged with Vibrio alginolyticus, the transcripts of PtA2Ms showed similar time-dependent response expression pattern, while PtA2M-1 was more sensitive to Micrococcus luteus and Pichia pastoris infection than PtA2M-2. Knockdown of PtA2M-1 or PtA2M-2 could significantly enhance the expression of prophenoloxidase (proPO) associated genes (PtproPO and PtPPAF) and serine protease related genes (PtcSP1-3 and PtSPH), however, PtLSZ and the phagocytosis-related genes (PtMyosin and PtRab5) were effectively inhibited. These results were further supported by the PO and lysozyme activities in hemolymph of the PtA2M-1- or PtA2M-2-silenced crabs. In addition, PtA2M-1 and PtA2M-2 could regulate the expression of antimicrobial peptide (AMP) genes (PtALF1-3, PtCrustin1 and PtCrustin3) through the Toll and NF-κB pathways. Our findings together suggest that PtA2Ms might function in crab host defense via regulating the proPO system, phagocytosis and the expression of AMP genes.


Assuntos
Braquiúros/genética , Braquiúros/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , alfa 2-Macroglobulinas Associadas à Gravidez/genética , alfa 2-Macroglobulinas Associadas à Gravidez/imunologia , Sequência de Aminoácidos , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Braquiúros/enzimologia , Catecol Oxidase/metabolismo , Precursores Enzimáticos/metabolismo , Perfilação da Expressão Gênica , Fagocitose/genética , Filogenia , alfa 2-Macroglobulinas Associadas à Gravidez/química , Alinhamento de Sequência
20.
Fish Shellfish Immunol ; 89: 632-640, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30995542

RESUMO

Iron homeostasis is vital to organismal health; it is maintained by the iron regulatory protein (IRP)-iron-responsive element (IRE) signaling pathway. In the Chinese mitten crab Eriocheir sinensis, EsFer-1 and EsFer-2 reportedly have a putative IRE, but an IRP has not yet been identified. In this study, we successfully amplified the full-length cDNA of EsIRP using gene cloning and rapid amplification of cDNA ends techniques. The length of this cDNA was 4474 bp, and it included a 2682-bp open reading frame encoding 893 amino acids. Using quantitative real-time PCR, mRNA transcripts of EsIRP were detected in various tissues. The highest and lowest expression level was detected in the muscle and gills, respectively. In response to Staphylococcus aureus and Vibrio parahaemolyticus challenge, the transcription level of EsIRP was downregulated and that of EsFer-1 and EsFer-2 was upregulated in hemocytes. EsIRP knockdown resulted in increased expression of both EsFer-1 and EsFer-2. After EsFer-1 and EsFer-2 knockdown, the bacterial clearance ability of E. sinensis against S. aureus and V. parahaemolyticus was impaired. In conclusion, our results suggest that the IRP-IRE signaling pathway plays an important role in the innate immune system response in E. sinensis.


Assuntos
Braquiúros/genética , Braquiúros/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Proteínas Reguladoras do Ferro/genética , Proteínas Reguladoras do Ferro/imunologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Perfilação da Expressão Gênica , Proteínas Reguladoras do Ferro/química , Masculino , Filogenia , Alinhamento de Sequência , Staphylococcus aureus/fisiologia , Vibrio parahaemolyticus/fisiologia
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