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1.
Mar Drugs ; 19(3)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804177

RESUMO

Chitin is among the most important components of the crustacean cuticular exoskeleton and intestinal peritrophic matrix. With the progress of genomics and sequencing technology, a large number of gene sequences related to chitin metabolism have been deposited in the GenBank database in recent years. Here, we summarized the genes and pathways associated with the biosynthesis and degradation of chitins in crustaceans based on genomic analyses. We found that chitin biosynthesis genes typically occur in single or two copies, whereas chitin degradation genes are all multiple copies. Moreover, the chitinase genes are significantly expanded in most crustacean genomes. The gene structure and expression pattern of these genes are similar to those of insects, albeit with some specific characteristics. Additionally, the potential applications of the chitin metabolism genes in molting regulation and immune defense, as well as industrial chitin degradation and production, are also summarized in this review.


Assuntos
Quitina/biossíntese , Quitinases/genética , Crustáceos/metabolismo , Animais , Quitina/genética , Quitina/metabolismo , Crustáceos/genética , Genômica , Muda/genética
2.
Zoolog Sci ; 38(1): 51-59, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33639718

RESUMO

In vertebrates, gonadotropin-releasing hormone (GnRH) regulates gonadal maturation by stimulating the synthesis and release of pituitary gonadotropins. GnRH has also been identified in invertebrates. Crustacea consists of several classes including Cephalocarida, Remipedia, Branchiopoda (e.g., tadpole shrimp), Hexanauplia (e.g., barnacle) and Malacostraca (e.g., shrimp, crab). In the malacostracan crustaceans, the presence of GnRH has been detected in several species, mainly by immunohistochemistry. In the present study, we examined whether a GnRH-like peptide exists in the brain and/or nerve ganglion of three classes of crustaceans, the tadpole shrimp Triops longicaudatus (Branchiopoda), the barnacle Balanus crenatus (Hexanauplia), and the hermit crab Pagurus filholi (Malacostraca), by immunohistochemistry using a rabbit polyclonal antibody raised against chicken GnRH-II (GnRH2). This antibody was found to recognize the giant freshwater prawn Macrobrachium rosenbergii GnRH (MroGnRH). In the tadpole shrimp, GnRH-like-immunoreactive (ir) cell bodies were located in the circumesophageal connective of the deuterocerebrum, and GnRH-like-ir fibers were detected also in the ventral nerve cord. In the barnacle, GnRH-like-ir cell bodies and fibers were located in the supraesophageal ganglion (brain), the subesophageal ganglion, and the circumesophageal connective. In the hermit crab, GnRH-like-ir cell bodies were detected in the anterior-most part of the supraesophageal ganglion and the subesophageal ganglion. GnRH-like-ir fibers were observed also in the thoracic ganglion and the eyestalk. These results suggest that a GnRH-like peptide exists widely in crustacean species.


Assuntos
Crustáceos/anatomia & histologia , Crustáceos/metabolismo , Gânglios/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Animais , Imuno-Histoquímica , Peptídeos/análise
3.
Ecotoxicol Environ Saf ; 197: 110626, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32339959

RESUMO

The objective of this study was to evaluate the tissue distributions of antibiotics in the fish, the bioaccumulation and trophic transfer in freshwater food web in Taihu Lake, a large shallow freshwater lake. Twenty four out of 41 antibiotics were detected in the biotas of the food web; and antibiotic concentrations followed the orders: fish plasma ~ fish muscle < fish liver ~ fish bile and fish < invertebrates ~ plankton. Antibiotic concentrations in the liver of piscivores were higher than those in omnivores and planktivores. Most bioaccumulation factors (BAFs) of sulfonamides (SAs), macrolides (MLs), ionophores (IPs) and lincomycin (LIN) were less than 2000 L/kg, indicating low bioaccumulation ability of these compounds in fish. Fluoroquinolones (FQs) were frequently detected in fish liver, invertebrates and plankton with much of BAFs great than 5000 L/kg, indicating that FQs have the potential of bioaccumulation in fish. Relationship analysis between BAFs and physicochemical properties of antibiotics showed that the bioaccumulation of antibiotics in the biota was related with their adsorption ability. Generally, the antibiotics in the food web of Lake Taihu including plankton, invertebrates and fish showed trophic dilution. The normalized estimated daily intake (EDI) values are less than the acceptable daily intake (ADI) values, and then hazard quotients were much less than 1. This result suggests the consumption of fish, crab and shrimp in Lake Taihu would probably not pose direct detrimental effects on humans.


Assuntos
Antibacterianos/análise , Organismos Aquáticos/metabolismo , Monitoramento Ambiental/métodos , Lagos/química , Poluentes Químicos da Água/análise , Animais , Antibacterianos/farmacocinética , Organismos Aquáticos/efeitos dos fármacos , China , Crustáceos/metabolismo , Peixes/metabolismo , Cadeia Alimentar , Humanos , Plâncton/metabolismo , Medição de Risco , Poluentes Químicos da Água/farmacocinética
4.
Subcell Biochem ; 94: 35-62, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32189295

RESUMO

Lipoproteins mediate the transport of apolar lipids in the hydrophilic environment of physiological fluids such as the vertebrate blood and the arthropod hemolymph. In this overview, we will focus on the hemolymph lipoproteins in Crustacea that have received most attention during the last years: the high density lipoprotein/ß-glucan binding proteins (HDL-BGBPs), the vitellogenins (VGs), the clotting proteins (CPs) and the more recently discovered large discoidal lipoproteins (dLPs). VGs are female specific lipoproteins which supply both proteins and lipids as storage material for the oocyte for later use by the developing embryo. Unusual within the invertebrates, the crustacean yolk proteins-formerly designated VGs-are more related to the ApoB type lipoproteins of vertebrates and are now termed apolipocrustaceins. The CPs on the other hand, which are present in both sexes, are related to the (sex specific) VGs of insects and vertebrates. CPs serve in hemostasis and wound closure but also as storage proteins in the oocyte. The HDL-BGBPs are the main lipid transporters, but are also involved in immune defense. Most crustacean lipoproteins belong to the family of the large lipid transfer proteins (LLTPs) such as the intracellular microsomal triglyceride transfer protein, the VGs, CPs and the dLPs. In contrast, the HDL-BGBPs do not belong to the LLTPs and their relationship with other lipoproteins is unknown. However, they originate from a common precursor with the dLPs, whose functions are as yet unknown. The majority of lipoprotein studies have focused on decapod crustaceans, especially shrimps, due to their economic importance. However, we will present evidence that the HDL-BGBPs are restricted to the decapod crustaceans which raises the question as to the main lipid transporting proteins of the other crustacean groups. The diversity of crustaceans lipoproteins thus appears to be more complex than reflected by the present state of knowledge.


Assuntos
Crustáceos , Hemolinfa , Lipoproteínas , Animais , Crustáceos/química , Crustáceos/imunologia , Crustáceos/metabolismo , Hemolinfa/química , Hemolinfa/imunologia , Hemolinfa/metabolismo , Lipoproteínas/biossíntese , Lipoproteínas/química , Lipoproteínas/imunologia , Lipoproteínas/metabolismo
5.
Mar Pollut Bull ; 154: 111045, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32174496

RESUMO

Concentrations of trace elements (arsenic, cadmium, mercury, and lead) in tissues (muscle, gills, and digestive gland) of three commercially exploited crustaceans (Portunus sanguinolentus, Charybdis natator, and Penaeus semisulcatus) and three cephalopods (Doryteuthis sibogae, Sepia pharaonis, and Cistopus indicus) were examined. The animals were captured in the waters of Thoothukudi, and the tissues of six individuals of each species were analyzed using ICP-MS. The highest concentrations of arsenic (16.5 µg/g) and mercury (0.052 µg/g) were recorded in the digestive gland of C. natator, and cadmium (69.9 µg/g) and lead (0.351 µg/g) in the digestive gland of S. pharaonis. The edible portion of the crustaceans and cephalopods contained lower concentrations of trace elements, and these were below allowable limits set by the European Union. The edible parts of the investigated samples are safe for human consumption, but accidental contamination of the edible tissues with material from the digestive glands could lead to concerns relating to metal toxicity.


Assuntos
Cefalópodes/metabolismo , Crustáceos/metabolismo , Mercúrio , Oligoelementos/metabolismo , Poluição da Água/estatística & dados numéricos , Animais , Cádmio , Monitoramento Ambiental , Contaminação de Alimentos/estatística & dados numéricos , Humanos , Índia , Alimentos Marinhos/estatística & dados numéricos
6.
Arch Environ Contam Toxicol ; 78(4): 589-603, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32020255

RESUMO

This is the first comprehensive report on the accumulation of Cr, Ni, As, and Ag in the fish species Nile tilapia Oreochromis niloticus and Nile perch Lates niloticus from Lake Victoria, complemented with recent data on Cu, Zn, Cd, and Pb. This also is the first report on Cr, Ni, As, and Ag levels in invertebrates: the shrimp Caridina nilotica, gastropod Pila ovata, and bivalve Mutela bourguignati. The study was conducted at five sites in the Kenyan part of Lake Victoria: four sites in Winam Gulf influenced by various anthropogenic pressures, including a site near Kisumu City, and one in the main lake, with lesser direct anthropogenic influence. Apart from Cu and Ag, which were highest in O. niloticus liver, the invertebrates had higher levels of trace elements than fish. Contamination of the gulf with trace elements was best mirrored by the invertebrates, whose mobility is limited; they accumulated Cr, Cd, Ag, and Pb corresponding to the levels in the surface sediment. The accumulation of trace elements in fish species and their bioindicative potential corresponded to their habitats and feeding behaviour. The tissue contents of most trace elements were higher in the inshore-dwelling, omnivorous O. niloticus compared to the pelagic, piscivorous L. niloticus. Cu (465 ± 689 mg/kg dw) and Ag (3.45 ± 1.49 mg/kg dw) in the liver of O. niloticus were up to 10 and 119 times higher than in L. niloticus, respectively. Oreochromis niloticus therefore has bioindicative potential for Cu and Ag contamination. Both the invertebrates and fish showed positive correlations between Cu and Ag concentrations, indicating similar source and/or uptake route. The target hazard quotients (THQ) show that there is no human health risk associated with the consumption of these fish. However, the levels of Zn, Cd, and Pb in P. ovata surpassed maximum food safety limits and are hence potentially unsafe for human consumption.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Bioacumulação , Biomarcadores Ambientais/efeitos dos fármacos , Monitoramento Ambiental/métodos , Lagos/química , Metais Pesados/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise , Animais , Organismos Aquáticos/metabolismo , Ciclídeos/metabolismo , Crustáceos/metabolismo , Humanos , Quênia , Metais Pesados/metabolismo , Moluscos/metabolismo , Percas/metabolismo , Medição de Risco , Alimentos Marinhos/análise , Oligoelementos/metabolismo , Poluentes Químicos da Água/metabolismo
7.
Molecules ; 25(3)2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32033085

RESUMO

Bioremediation of soils polluted with petroleum compounds is a widely accepted environmental technology. We compared the effects of biostimulation and bioaugmentation of soil historically contaminated with aliphatic and polycyclic aromatic hydrocarbons. The studied bioaugmentation treatments comprised of the introduction of differently developed microbial inoculants, namely: an isolated hydrocarbon-degrading community C1 (undefined-consisting of randomly chosen degraders) and a mixed culture C2 (consisting of seven strains with well-characterized enhanced hydrocarbon-degrading capabilities). Sixty days of remedial treatments resulted in a substantial decrease in total aliphatic hydrocarbon content; however, the action of both inoculants gave a significantly better effect than nutrient amendments (a 69.7% decrease for C1 and 86.8% for C2 vs. 34.9% for biostimulation). The bioaugmentation resulted also in PAH removal, and, again, C2 degraded contaminants more efficiently than C1 (reductions of 85.2% and 64.5%, respectively), while biostimulation itself gave no significant results. Various bioassays applying different organisms (the bacterium Vibrio fischeri, the plants Sorghum saccharatum, Lepidium sativum, and Sinapis alba, and the ostracod Heterocypris incongruens) and Ames test were used to assess, respectively, potential toxicity and mutagenicity risk after bioremediation. Each treatment improved soil quality, however only bioaugmentation with the C2 treatment decreased both toxicity and mutagenicity most efficiently. Illumina high-throughput sequencing revealed the lack of (C1) or limited (C2) ability of the introduced degraders to sustain competition from indigenous microbiota after a 60-day bioremediation process. Thus, bioaugmentation with the bacterial mixed culture C2, made up of identified, hydrocarbon-degrading strains, is clearly a better option for bioremediation purposes when compared to other treatments.


Assuntos
Bactérias/metabolismo , Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Animais , Biodegradação Ambiental , Crustáceos/metabolismo , Lepidium sativum , Sinapis/metabolismo , Solo/química , Microbiologia do Solo , Sorghum/metabolismo
8.
Mar Drugs ; 18(2)2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32019265

RESUMO

: Chitin is one of the most abundant biomolecules on earth, occurring in crustacean shells and cell walls of fungi. While the polysaccharide is threatening to pollute coastal ecosystems in the form of accumulating shell-waste, it has the potential to be converted into highly profitable derivatives with applications in medicine, biotechnology, and wastewater treatment, among others. Traditionally this is still mostly done by the employment of aggressive chemicals, yielding low quality while producing toxic by-products. In the last decades, the enzymatic conversion of chitin has been on the rise, albeit still not on the same level of cost-effectiveness compared to the traditional methods due to its multi-step character. Another severe drawback of the biotechnological approach is the highly ordered structure of chitin, which renders it nigh impossible for most glycosidic hydrolases to act upon. So far, only the Auxiliary Activity 10 family (AA10), including lytic polysaccharide monooxygenases (LPMOs), is known to hydrolyse native recalcitrant chitin, which spares the expensive first step of chemical or mechanical pre-treatment to enlarge the substrate surface. The main advantages of enzymatic conversion of chitin over conventional chemical methods are the biocompability and, more strikingly, the higher product specificity, product quality, and yield of the process. Products with a higher Mw due to no unspecific depolymerisation besides an exactly defined degree and pattern of acetylation can be yielded. This provides a new toolset of thousands of new chitin and chitosan derivatives, as the physio-chemical properties can be modified according to the desired application. This review aims to provide an overview of the biotechnological tools currently at hand, as well as challenges and crucial steps to achieve the long-term goal of enzymatic conversion of native chitin into specialty chemical products.


Assuntos
Biotecnologia , Quitina/química , Quitosana/química , Animais , Quitina/isolamento & purificação , Quitina/metabolismo , Quitosana/metabolismo , Crustáceos/metabolismo , Ecossistema , Fungos/metabolismo
9.
Food Chem ; 309: 125706, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31677450

RESUMO

Electrochemistry of carotenoids has attracted a lot of interest because it provides an understanding of their oxidative properties. We report the application of electrochemistry in the analysis of carotenoids. Voltammetry of microdroplets immobilized on paraffin impregnated graphite electrode in 0.1 mol dm-3 HClO4 and KNO3 aqueous electrolytes using square-wave voltammetry was applied. Previous studies have shown that carotenoids undergo complex oxidation process when characterized in aqueous media. In this research, the electrooxidation of carotenoid astaxanthin was confirmed. The obtained response allowed the development of an electroanalytical method with a limit of detection of 15.77 µmol dm-3, the limit of quantification of 47.80 µmol dm-3 and acceptable relative standard deviations for current (3.69%) and potential (0.41%). Extraction using DMSO and acetone has shown to be appropriate for voltammetric analysis. Astaxanthin content was determined electrochemically in shrimp and soft-shell crab samples (20.63 and 6.59 µg g-1, respectively), yielding recoveries above 90%.


Assuntos
Carotenoides/análise , Crustáceos/química , Técnicas Eletroquímicas/métodos , Animais , Crustáceos/metabolismo , Dieta , Eletrodos , Grafite/química , Humanos , Limite de Detecção , Oxirredução , Alimentos Marinhos/análise , Água/química , Xantofilas/análise , Xantofilas/química
10.
Carbohydr Polym ; 228: 115382, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31635752

RESUMO

Chitins of different purity grades (45%, 89.7% and 93.3%) were efficiently extracted from Bombyx eri larva and fully physico-chemically characterized. Compared to commercially available and extracted α-chitin from shrimp shell, the collected data showed that insect chitins had similar characteristics in terms of crystallographic structures (α-chitin), thermal stability and degree of acetylation (>87%). The major differences lay in the crystallinity indexes (66% vs 75% for shrimp chitin) and in the morphological structures. Furthermore, low ash contents were determined for the insect chitins (1.90% vs 21.73% for shrimp chitin), making this chitin extraction and purification easier, which is highly valuable for an industrial application. Indeed, after only one step (deproteinization), the obtained chitin from Bombyx eri showed higher purity grade than the one extracted from shrimp shells under the same conditions. Insect chitins were then subjected to room temperature ionic liquid (RTIL) pretreatment prior to enzymatic degradation and presented a higher enzymatic digestibility compared to commercial one whatever their purity grade and would be thus a more relevant source for the selective production of N-acetyl-D-glucosamine (899.2 mg/g of chitin-2 stepsvs 760 mg/g of chitin com). Moreover, for the first time, the fermentescibility of chitin hydrolysates was demonstrated with Scheffersomyces stipitis used as ethanologenic microorganism.


Assuntos
Bombyx/metabolismo , Quitina , Crustáceos/metabolismo , Animais , Quitina/química , Quitina/isolamento & purificação , Larva/metabolismo
11.
Environ Sci Process Impacts ; 21(11): 1980-1990, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31553340

RESUMO

Per- and polyfluoroalkyl substances (PFASs) are frequently detected in aquatic environments. Longer chained perfluoroalkyl acids (PFAAs), in particular, have been found to bioaccumulate in a broad range of aquatic biota. PFAAs have a physiochemical similarity to naturally occurring fatty acids and could potentially disrupt metabolic processes, however, there has been limited study in this area, especially in aquatic species. In this study, the associations between PFAAs and metabolite profiles were investigated in crustaceans. Eastern School Prawn (Metapenaeus macleayi) were obtained from three different locations (n = 15 per location) with similar environmental conditions but different levels of PFAA contamination. The concentrations of PFAAs, fatty acids and amino acids were analysed and differences in PFAA and metabolite profiles were evaluated. Different PFAA profiles were mirrored by significant differences in the composition of both fatty acid and amino acid profiles, indicating a potential association between PFAA concentration and the composition of metabolites in prawns. These results highlight a need for further research investigating the impacts of PFAA exposure, with the current study providing a foundation for further investigation of the relationship between PFAA bioaccumulation and organism metabolism.


Assuntos
Organismos Aquáticos/química , Crustáceos/química , Monitoramento Ambiental/métodos , Fluorcarbonetos/toxicidade , Metaboloma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Aminoácidos/metabolismo , Animais , Organismos Aquáticos/metabolismo , Crustáceos/metabolismo , Ácidos Graxos/metabolismo , Fluorcarbonetos/análise , Metabolômica , New South Wales , Poluentes Químicos da Água/análise
12.
J Biol Chem ; 294(44): 16440-16450, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31537644

RESUMO

Alternatively-spliced hypervariable immunoglobulin domain-encoding molecules, called Down syndrome cell adhesion molecule (Dscam), have been widely detected as components of the arthropod immune system. Although its ability to specifically bind pathogens and enable phagocytosis of bacteria has been elucidated, the signal transduction mechanisms or effectors that activate post-Dscam-binding pathogens remain poorly characterized. Here, we reveal the alternative splicing exons of Dscam's cytoplasmic tail and its isoforms in the hemocytes of crab (Eriocheir sinensis), showing that the expression of Dscam was acutely induced after an immune challenge, which suggested its functioning for innate immunity. Significantly decreased expression levels of antimicrobial molecular peptides (AMPs) were detected in Dscam-silenced crab hemocytes in vitro, which coincided with their vulnerability to infection by Staphylococcus aureus and higher bacterial concentrations occurring in Dscam-silenced crabs in vivo Further experimental investigation demonstrated that Dscam-regulated AMP expression via the Src homology (SH)3-binding domain in the first constant exon translated protein of the cytoplasmic tail bound with the SH3 domain of the Dock, an SH3/SH2 adaptor protein required for axon guidance. Dock promoted extracellular signal-regulated kinase (ERK) phosphorylation via indirect binding and then regulated dorsal phosphorylation and translocation from the cytoplasm to the nucleus, subsequently promoting AMP expression for the effective removal of bacteria. To the best of our knowledge, this comprehensive study is the first to highlight the critical role of the alternatively-spliced Dscam cytoplasmic tail in antimicrobial control activity. It also suggests possible cross-talk occurring between Dscam and other pattern recognition receptors.


Assuntos
Braquiúros/genética , Braquiúros/imunologia , Moléculas de Adesão Celular/metabolismo , Imunidade Inata/fisiologia , Processamento Alternativo/genética , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/metabolismo , Moléculas de Adesão Celular/genética , Crustáceos/metabolismo , Éxons , Hemócitos/metabolismo , Imunidade Inata/genética , Fagocitose , Filogenia , Isoformas de Proteínas/metabolismo , Processamento de RNA/genética , Alinhamento de Sequência , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo
13.
Chemosphere ; 237: 124551, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31549662

RESUMO

To characterize the potential endocrine-disrupting chemicals (EDCs) in the environment that interact with the crustacean ecdysone receptor (EcR), we established a method involving in silico modeling/molecular docking and in vitro reporter gene assay. Cherry shrimp (Neocaridina davidi) EcR (NdEcR) and retinoid X receptor (NdRxR) were identified and cloned for use in this method. A theoretical 3D model of NdEcR ligand-binding domain (LBD) was built in silico based on sequence homology with the established X-ray structure of insect EcR. The interaction of the NdEcR LBD with ecdysteroids, diacylhydrazine (DAH) pesticides, and other potential EDCs was evaluated using molecular docking programs. The results revealed that the ligand-binding pocket in the NdEcR LBD was flexible and adaptive for accommodating ligands of different shapes. The agonistic and antagonistic activities of the candidate compounds were further assessed by in vitro reporter gene assay using human cell lines transiently transfected with NdEcR and NdRxR expression plasmids and a reporter plasmid containing synthesized ecdysone response element. The assay was validated by the dose-dependent responses of EcR-mediated gene transcription after treating the transfected cell lines with ecdysteroids, 20-hydroxyecdysone, and ponasterone A. Examination of the candidate compounds using the reporter gene assay revealed restricted functional specificity to ecdysteroids and DAHs. Three of the tested DAH pesticides originally targeting the insect EcR were found to be weak agonists and strong antagonists of NdEcR. These results suggest that DAHs are potential EDCs for crustaceans that disrupt their ecdysteroid signals by functioning as EcR agonists or antagonists.


Assuntos
Crustáceos/efeitos dos fármacos , Ecdisteroides/farmacologia , Praguicidas/toxicidade , Receptores de Esteroides/metabolismo , Animais , Sítios de Ligação , Linhagem Celular , Simulação por Computador , Crustáceos/metabolismo , Decápodes/genética , Ecdisona/metabolismo , Ecdisona/farmacologia , Ecdisteroides/toxicidade , Ecdisterona/análogos & derivados , Ecdisterona/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Humanos , Simulação de Acoplamento Molecular , Praguicidas/química , Praguicidas/metabolismo , Filogenia , Receptores de Esteroides/agonistas , Receptores de Esteroides/antagonistas & inibidores , Receptores de Esteroides/genética , Receptores X Retinoide/química , Receptores X Retinoide/genética , Receptores X Retinoide/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-31419604

RESUMO

Low temperature reduction is thought to cause widespread effects on the physical and behavioral traits of marine organisms, which include metabolic processes, immune responses, and reproductive behavior. Crustaceans are generally considered sensitive to temperature reduction due to the lack of efficient regulators. To better understand the molecular regulatory mechanisms of crustacean exposure to cold stress, Japanese mantis shrimp (Oratosquilla oratoria) was chosen as a representative crustacean. Transcriptomic responses in O. oratoria from five temperatures (25 °C, 22 °C, 19 °C, 16 °C, and 13 °C) were studied using RNA-seq. A total of 64.91 Gb of clean transcriptomic data were generated in 10 libraries and then spliced into 52,107 unigenes with an average length of 1089 bp and an N50 length of 1872 bp. A total of 14,841 unigenes was annotated in at least one database using Blastx alignment. Compared with the control temperature (25 °C), 7, 21, 58, and 236 unigenes were significantly differentially expressed at 22 °C, 19 °C, 16 °C, and 13 °C, respectively. GO analysis showed that 6, 20, 27, and 35 terms were significantly enriched at 22 °C, 19 °C, 16 °C, and 13 °C, respectively. In addition, 2, 5, 2, and 10 significant pathways were presented at 22 °C, 19 °C, 16 °C, and 13 °C, respectively. Combining NR, GO, and KEGG annotation information, many genes significantly differentially expressed at low temperatures may be associated with metabolic processes, immune response, and reproductive behavior. Additionally, we reconstructed the phylogenetic relationship based on 366 orthologous genes and the predicted differentiation time of O. oratoria and P. vannamei range from 212.82 to 365.30 Mya. Furthermore, 16 orthologous genes were identified as PSGs and 30 orthologous genes were identified as FEGs and these adaptive genes were associated with energy metabolism, stress response and immunity, and multiple cellular processing. These results provide fundamental information about molecular mechanisms regulating cold stress response of O. oratoria.


Assuntos
Temperatura Baixa , Crustáceos/fisiologia , Perfilação da Expressão Gênica , Músculos/metabolismo , Animais , Metabolismo dos Carboidratos , Crustáceos/genética , Crustáceos/imunologia , Crustáceos/metabolismo , Metabolismo dos Lipídeos , Filogenia , Reprodução
15.
J Morphol ; 280(8): 1170-1184, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31141207

RESUMO

The Japanese mantis shrimp Oratosquilla oratoria (Stomatopoda; Crustacea) is one of the most economically important aquatic species of Pacific shrimp and it is distributed from Japan to the coast of China, the Philippines, the Malay Peninsula, and the Hawaiian Islands. Early studies described certain characteristics of spermatogenesis and the sperm ultrastructure in Stomatopoda, but the composition of sperm basic nuclear proteins (SBNPs) remains completely unknown. We studied the sperm ultrastructure of O. oratoria using transmission electron microscopy and the histone composition using immunofluorescence and immunoelectron microscopy. We found that the spherical nucleus is adjacent to the electron translucent external coat, which occurs in early spermatids. The acrosomal structure begins to form at the junction of the nucleus and the external coat. At the mid-spermatid stage, part of the chromatin appears to be more electron-dense than the external coat side. The aflagellate sperm of O. oratoria, are rounded or slightly ovoid in shape and have a consistent granular nucleus, an acrosome structure of pushpin shape and a spherical vesicular body in which faintly granular material is scattered. The acrosome consists of an acrosomal vesicle, perforatorium, and subacrosomal material. The sperm contains histones H2A, H2B, H3, H4, H3.3, H2AX, and H2AZ as well as some histone modifications, that is, H3K9me3, H3K4me2, H3S10ph, H4Kac, and H2A + H4S1ph. Histones are localized not only in the nucleus of the sperm but also in other structures outside the nucleus. The results may provide new perspectives for systematic studies of crustaceans and their sperm chromatin components. These findings extend the study of the sperm structure of Stomatopoda and provide basic data to elucidate the epigenetic mechanism of fertilization.


Assuntos
Núcleo Celular/metabolismo , Crustáceos/metabolismo , Histonas/metabolismo , Espermatogênese , Espermatozoides/ultraestrutura , Animais , Núcleo Celular/ultraestrutura , Cromatina/metabolismo , Cromatina/ultraestrutura , Crustáceos/ultraestrutura , Masculino , Processamento de Proteína Pós-Traducional , Espermátides/ultraestrutura , Espermatozoides/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-30858099

RESUMO

Farnesoic acid O-methyltransferase (FAMeT) is a key enzyme involved in catalyzing the conversion of farnesoic acid (FA) to methylfarnesoate (MF) in the mandibular organ (MO) of crustaceans. In this study, a full-length cDNA encoding a 278-amino-acid FAMeT protein (MrFAMeT) was characterized from the giant freshwater prawn, Macrobrachium rosenbergii. Bioinformatics analysis revealed a high degree of conservation of FAMeT among crustaceans and a close phylogenetic relationship between MrFAMeT and that of Scylla paramamosain. The prokaryotic expressed MrFAMeT could catalyze the conversion of FA to MF in a radiochemical assay. Expression analysis by quantitative real time reverse transcription polymerase chain reaction (qRT-PCR) demonstrated that MrFAMeT mRNA was highly expressed in the muscle and the hepatopancreas of both females and males. During the molt cycle and the ovarian development, the mRNA expressions of MrFAMeT displayed stage-specific patterns in the muscle of both sexes and the female hepatopancreas, and the highest expressions were detected at intermolt and ovarian development stage V. Double stranded RNA (dsRNA)-mediated RNA interference (RNAi) of MrFAMeT increased expressions of myostatin in the muscle of both sexes and reduced expressions of vitellogenin (Vg) in the female hepatopancreas. Furthermore, both in the muscle and the hepatopancreas, silence of MrFAMeT downregulated the expression of ecydone receptor gene (MrEcR) and silence of MrEcR decreased the expression of MrFAMeT as well. Results in our study indicate that MrFAMeT is involved in prawn muscle growth and female vitellogenin biosynthesis and its function may be closely related with the ecdysteroid signaling.


Assuntos
Crustáceos/metabolismo , Ecdisteroides/metabolismo , Metiltransferases/metabolismo , Transdução de Sinais , Animais , Catálise , Hepatopâncreas/metabolismo , Músculos/metabolismo
17.
Artigo em Inglês | MEDLINE | ID: mdl-30735703

RESUMO

Although widely known for their involvement in the control of carbohydrate and lipid metabolism of vertebrates, the participation of catecholamines (CAs) in the metabolism of invertebrates is less understood. This study was designed to identify the physiological role of Epinephrine (E) in the intermediary metabolism of the burrowing crab Neohelice granulata and how E regulates the metabolism in crabs fed with a high-carbohydrate (HC) or a high-protein (HP) diet. To answer these questions, we evaluated in vivo the effects of E injections on glucose and triglycerides in the hemolymph and tissue glycogen levels of crabs fed with HC or HP diet. An in vitro investigation was carried out to assess the direct effects of E on glycogenolysis, lipolysis and glycolysis pathways in the hepatopancreas, mandibular muscle and anterior and posterior gills of this crab. E injections increased glucose and did not affect triglycerides levels in the hemolymph of either group of crabs, and E decreased glycogen in the hepatopancreas and mandibular muscle only in HP crabs, suggesting that these effects may be mediated by the crustacean hyperglycemic hormone (CHH). When the tissues were incubated with different concentrations of E, the concentration of glucose released to the medium decreased in the hepatopancreas and posterior gills, while glucose oxidation increased in the posterior gills of HP crabs. Incubation with E did not alter any parameter in tissues of HC crabs. These effects suggest that E may be involved in the metabolic response to osmotic stress.


Assuntos
Crustáceos/efeitos dos fármacos , Epinefrina/farmacologia , Animais , Crustáceos/metabolismo , Carboidratos da Dieta/administração & dosagem , Proteínas na Dieta/administração & dosagem , Glucose/metabolismo , Glicogênio/metabolismo , Hemolinfa/efeitos dos fármacos , Hemolinfa/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Oxirredução
18.
Artigo em Inglês | MEDLINE | ID: mdl-30690149

RESUMO

Crustacean hyperglycemic hormone (CHH) plays a crucial role in regulating carbohydrate metabolism in crustaceans. In this study, a new cDNA encoding type I CHH peptide, termed Sp-CHH3, was isolated from the mud crab Scylla paramamosain and its potential functions were investigated. The full length cDNA of Sp-CHH3 was identified as encoding a 127-aa precursor composed of a 27-aa signal peptide, a 23-aa CHH precursor-related peptide and a 75-aa mature peptide with a typical motif of CHH. Phylogenic analysis suggested that, Sp-CHH3 is a previously unreported CHH from S. paramamosain. Tissue distribution analysis showed that Sp-CHH3 was mainly expressed in the eyestalk ganglia, thoracic ganglia, stomach and the ovary. A RNA interference experiments showed that after injection of Sp-CHH3-targeted dsRNA, both the level of Sp-CHH3 expression in the eyestalk ganglia and hemolymph glucose level decreased significantly. A further short-term starvation experiments demonstrated that, the level of Sp-CHH3 detected in the eyestalk ganglia was significantly up-regulated at the 12th h of starvation, it then fell back at the 24th h of starvation and subsequently remained relative stability between the 24th to 96th h of starvation. The hemolymph glucose level decreased significantly (P < .05) at each sampling time during the 96 h starvation duration when compared to that of 0 h (prior to starvation) and the overall trend was largely correlated with the level of Sp-CHH3 expression in the eyestalk ganglia. In summary, the results suggest that Sp-CHH3 plays a functional role in regulating carbohydrate metabolism in S. paramamosain.


Assuntos
Proteínas de Artrópodes/fisiologia , Metabolismo dos Carboidratos/fisiologia , Crustáceos/metabolismo , Hormônios de Invertebrado/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/genética , Sequência de Bases , Clonagem Molecular , Crustáceos/genética , DNA Complementar/genética , Hemolinfa/metabolismo , Hormônios de Invertebrado/genética , Proteínas do Tecido Nervoso/genética , Filogenia , Interferência de RNA , Inanição
19.
Neurosci Lett ; 695: 19-24, 2019 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-28711343

RESUMO

The many roles of innexins, the molecules that form gap junctions in invertebrates, have been explored in numerous species. Here, we present a summary of innexin expression and function in two small, central pattern generating circuits found in crustaceans: the stomatogastric ganglion and the cardiac ganglion. The two ganglia express multiple innexin genes, exhibit varying combinations of symmetrical and rectifying gap junctions, as well as gap junctions within and across different cell types. Past studies have revealed correlations in ion channel and innexin expression in coupled neurons, as well as intriguing functional relationships between ion channel conductances and electrical coupling. Together, these studies suggest a putative role for innexins in correlating activity between coupled neurons at the levels of gene expression and physiological activity during development and in the adult animal.


Assuntos
Conexinas/biossíntese , Sinapses Elétricas/metabolismo , Gânglios dos Invertebrados/metabolismo , Animais , Crustáceos/metabolismo , Junções Comunicantes/metabolismo , Atividade Motora/fisiologia , Neurônios/metabolismo
20.
Sci Total Environ ; 654: 250-263, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30447573

RESUMO

Scientists are currently faced with the challenge of assessing the effects of anthropogenic stressors on aquatic ecosystems. Cellular stress response (CSR) biomarkers are ubiquitous and phylogenetically conserved among metazoans and have been successfully applied in environmental monitoring but they can also vary according to natural biotic and abiotic factors. The reported variability may thus limit the wide application of biomarkers in monitoring, imposing the need to identify variability levels in the field. Our aim was to carry out a comprehensive in situ assessment of the CSR (heat shock protein 70 kDa, ubiquitin, antioxidant enzymes) and oxidative damage (lipid peroxidation) in wild populations across marine taxa by collecting fish, crustaceans, mollusks and cnidarians during two different seasons (spring and summer) and two habitat types (coast and estuary). CSR end-point patterns were different between taxa with mollusks having higher biomarker levels, followed by the cnidarians, while fish and crustaceans showed lower biomarker levels. The PCA showed clear clusters related to mobility/sessile traits with sessile organisms showing greater levels (>2-fold) of CSR proteins and oxidative damage. Mean intraspecific variability in the CSR measured by the coefficient of variation (% CV) (including data from all seasons and sites) was elevated (35-94%). Overall, there was a seasonal differentiation in biomarker patterns across taxonomic groups, especially evident in fish and cnidarians. A differentiation in biomarker patterns between habitat types was also observed and associated with phenotypic plasticity or local adaptation. Overall, specimens collected in the estuary had lower biomarker levels when compared to specimens collected in the coast. This work highlights the importance of assessing baseline biomarker levels across taxa, seasons and habitats prior to applying biomarker analyses in environmental monitoring. Selecting bioindicator species, defining sampling strategies, and identifying confounding factors are crucial preliminary steps that ensure the success of biomarkers as powerful tools in biomonitoring.


Assuntos
Organismos Aquáticos/classificação , Monitoramento Ambiental/métodos , Estresse Oxidativo/efeitos dos fármacos , Estações do Ano , Espécies Sentinelas/classificação , Poluentes Químicos da Água/análise , Animais , Organismos Aquáticos/efeitos dos fármacos , Argentina , Biomarcadores/análise , Cnidários/efeitos dos fármacos , Cnidários/metabolismo , Crustáceos/efeitos dos fármacos , Crustáceos/metabolismo , Ecossistema , Peixes/metabolismo , Moluscos/efeitos dos fármacos , Moluscos/metabolismo , Espécies Sentinelas/metabolismo , Poluentes Químicos da Água/toxicidade
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