RESUMEN
Neuronal responses to peptide signaling are determined by the specific binding of a peptide to its receptor(s). For example, isoforms of the same peptide family can drive distinct responses in the same circuit by having different affinities for the same receptor, by having each isoform bind to a different receptor, or by a combination of these scenarios. Small changes in peptide composition can alter the binding kinetics and overall physiological response to a given peptide. In the American lobster (Homarus americanus), native isoforms of C-type allatostatins (AST-Cs) usually decrease heartbeat frequency and alter contraction force. However, one of the three AST-C isoforms, AST-C II, drives a cardiac response distinct from the response elicited by the other two. To investigate the aspects of the peptide that might be responsible for these differential responses, we altered various features of each peptide sequence. Although the presence of an amide group at the end of a peptide sequence (amidation) is often essential for determining physiological function, we demonstrate that C-terminal amidation does not dictate the AST-C response in the lobster cardiac system. However, single amino acid substitution within the consensus sequence did account for many of the differences in specific response characteristics (e.g. contraction frequency or force).
Asunto(s)
Nephropidae , Neuropéptidos , Animales , Corazón , Nephropidae/metabolismo , Neuropéptidos/metabolismo , Péptidos/metabolismo , Isoformas de Proteínas/metabolismoRESUMEN
A new palaemonid shrimp genus, Opaepupu gen. nov., is established to accommodate a new species of bivalve-associated shrimp, Opaepupu huna sp. nov. from Hawaii. A single mated pair, the female holotype and the male allotype, were found inside the trapezid bivalve Trapezium oblongum (Linnaeus, 1758) at a depth of 14 m in Kâne'ohe Bay, Hawai'i. The new genus is characterised by the rostrum being proximally broad, distally pointed, mid-dorsally carinate, and non-dentate; the anterolateral margin of the carapace without supraorbital, hepatic or epigastric teeth, but with a strong sharp antennal tooth; the sixth pleonite posteriorly unarmed; the telson medially depressed, with the dorsal surface armed with two pairs of submarginal cuspidate setae and with the posterior margin armed with two pairs of spiniform setae; the distolateral angle of the first article of the antennular peduncle without a sharp tooth; the mandible without a palp; the maxillular palp furnished with one long stiff seta dorsal to a small tooth-like extension; the first maxilliped without a palp; the third maxilliped not being operculate; the second pereiopods moderately robust, relatively slender, subequal, subsymmetrical, with simple teeth on the cutting edges of the fingers; the ambulatory pereiopods being slender, each ending in an elongate biunguiculate dactylus; and the uropodal exopod with a faint diaeresis and greatly reduced distolateral spiniform seta. The phylogenetic position of Opaepupu gen. nov. remains unclear, although it does not appear to be closely related to other bivalve-associated palaemonid genera.
Asunto(s)
Bivalvos , Decápodos , Palaemonidae , Distribución Animal , Estructuras Animales , Animales , Femenino , Hawaii , Masculino , FilogeniaRESUMEN
The immunostimulatory potential of the marine yeast Yarrowia lipolytica (D1 and N6 strains) administered orally was evaluated in the white shrimp Litopenaeus vannamei. Yeasts and commercial glucans were mixed with a commercial feed to formulate diets with a 1.1% concentration of immunostimulants. The shrimp were fed daily for a period of 21 days. Weekly determinations were performed for immunological parameters in hemolymph, such as total hemocyte count (THC), lysozyme activity (LYZ), prophenoloxidase activity, antioxidant enzymatic activities (superoxide dismutase [SOD], catalase [CAT], and peroxidases), and bactericidal activity against Vibrio parahaemolyticus. Expression profiles of penaeidin (PEN), lysozyme (LYZ), and prophenoloxidase (proPO) immune genes were evaluated in hemocytes. In general, an increase in the immune parameters was observed in shrimp fed yeast diet compared to glucan and the control diets. Yarrowia lipolytica, especially strain N6, provided maximum immunostimulatory effects evidenced by the increase of immune parameters (THC, LYZ, SOD, CAT) and gene expression profile. In conclusion, this study demonstrated that Y. lipolytica had immunostimulatory effects and increased bactericidal activity in L. vannamei hemocytes against V. parahaemolyticus. These findings open the path for the potential application of Y. lipolytica-based immunostimulant for shrimp aquaculture.
Asunto(s)
Antioxidantes/metabolismo , Expresión Génica/inmunología , Inmunidad Humoral , Inmunidad Innata , Penaeidae/inmunología , Yarrowia/química , Levadura Seca/metabolismo , Alimentación Animal/análisis , Animales , Dieta/veterinaria , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Inmunidad Humoral/efectos de los fármacos , Inmunidad Innata/inmunología , Distribución Aleatoria , Levadura Seca/administración & dosificaciónRESUMEN
Manganese (Mn) is a hypoxic reactive metal commonly found in marine sediments. Under hypoxic conditions the metal becomes fully reduced to Mn2+ and is biologically available to the benthic community for uptake. Mn is also a potent neurotoxin and it may play a role in the etiology of idiopathic blindness that has been observed in American lobsters. An acute exposure study was designed to expose American lobster, Homarus americanus, to 0, 20, 80, 150, and 300â¯mgâ¯L-1 (ppm) for 96â¯hs to explore disparities in Mn accumulation among several tissues: optic nerve, brain, hepatopancreas, muscle, hemolymph, gill, and exoskeleton. These concentrations were based on realistic pore-water concentrations (20â¯mgâ¯L-1), high sediment concentrations (80â¯mgâ¯L-1), and unrealistically high concentrations to determine lethality (150 and 300â¯mgâ¯L-1). A positive correlation between Mn accumulation and exposure concentration was observed in all tissues examined. In the internal tissues, manganese concentrations showed a high affinity towards brain, optic nerve, and hemolymph. In the exoskeleton and gills, Mn concentrations were also high, possibly because of internal uptake as well as external adsorption. Concentrations of Mn in tissues from the acute exposure study followed the accumulation pattern: hemolymphâ¯>â¯gillâ¯>â¯exoskeletonâ¯>â¯optic nerveâ¯>â¯brainâ¯>â¯hepatopancreasâ¯=â¯muscle. A long-term exposure study lasting seven weeks was designed to investigate the potential link between high Mn exposure and idiopathic blindness, a condition that affects an estimated 50 % of the adult American lobster population off Southern New England (SNE), USA. A comparison of these exposure studies showed evidence of time-dependent Mn accumulation in brain, muscle, exoskeleton, and gill tissue. Although the relationship between Mn exposure and blindness was not apparent, there was a modest trend in the development of blindness (Chi-square, pâ¯=â¯0.102) in animals exposed to a high concentration (150â¯mgâ¯L-1) of the metal. With no mortalities occurring in the acute study and only one mortality in the long-term study, it is highly unlikely that Mn is acutely toxic to American lobsters at environmentally relevant concentrations. Its potential role in idiopathic blindness remains to be determined.
Asunto(s)
Ceguera/inducido químicamente , Hemolinfa/efectos de los fármacos , Manganeso/toxicidad , Nephropidae/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Branquias/metabolismo , Hemolinfa/metabolismo , Hepatopáncreas/efectos de los fármacos , Hepatopáncreas/metabolismo , Nephropidae/metabolismo , Pruebas de ToxicidadRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Lindernia crustacea (L.) F.Muell. (Scrophulariaceae) was selected for phytochemical investigation owing to its traditional use against human herpes virus infection and its anti-Epstein-Barr virus (EBV) effect. AIMS OF THE STUDY: The present study focused on the phytochemical investigation of L. crustacea including the isolation and structure determination of its biologically active compounds. Compounds with anti-EBV effects were also investigated. MATERIALS AND METHODS: The EtOH extract of L. crustacea was subsequently partitioned using different solvents. The EtOAc fraction was subjected to several chromatographic methods to obtain pure compounds. The structures of all isolates were established by spectroscopic analysis and compared with previously reported physical data. The anti-EBV effect was evaluated in an EBV-containing Burkitt's lymphoma cell line (P3HR1) to study the expression of EBV lytic proteins. RESULTS: Thirty-three compounds, including one diterpene (1), four anthraquinones (2-5), two ionones (6 and 7), fourteen phenylpropanoid glycosides (8-21), five flavonoids (22-26), one lignan glycoside (27), one phenethyl alcohol glycoside (28), one phenylpropene glycoside (29), one glucosyl glycerol derivative (30), one furanone (31), and two cinnamic acid derivatives (32 and 33), were isolated from the ethanolic extract of the plant. All isolated compounds were obtained for the first time from Lindernia sp. The evaluation of the anti-EBV activity of L. crustacea crude extract, partitioned fractions, and constituents was performed for the first time. Phytol (1), aloe-emodin (2), byzantionoside B (7), a mixture of trans-martynoside (8) and cis-martynoside (9), a mixture of trans-isomartynoside (10) and cis-isomartynoside (11), luteolin-7-O-ß-D-glucopyranoside (24), and apigenin-7-O-[ß-D-apiofuranosyl (1â6)-ß-D-glucopyranoside] (25) exhibited significant inhibitory effects on the EBV lytic cycle at 20 µg/mL in the immunoblot analysis. On the other hand, (6R,7E,9R)-3-oxo-α-ionol-ß-D-glucopyranoside (6) and a mixture of trans-dolichandroside A (12) and cis-dolichandroside A (13) showed moderate anti-EBV activity at 20 µg/mL. CONCLUSIONS: L. crustacea and its active isolates could be developed as potential candidates against EBV. Our findings provide scientific evidence for the traditional use of L. crustacea for its antiviral effects.
Asunto(s)
Antivirales/farmacología , Herpesvirus Humano 4/efectos de los fármacos , Extractos Vegetales/farmacología , Scrophulariaceae/química , Antivirales/aislamiento & purificación , Linfoma de Burkitt/virología , Línea Celular , Humanos , Proteínas Inmediatas-Precoces/genética , Transactivadores/genéticaRESUMEN
The hepatopancreas of isopods has major functions in food digestion and storage of carbohydrates and lipids. Also, it stores essential and accumulates xenobiotic metals in lysosomal granules within the two major cell types, the S- and B-cells of the tissue. A µCT study on moulting Porcellio scaber has shown mineral within the hepatopancreas lumen, when the animal has ingested their shed cuticle after moulting, suggesting recycling of mineral from the exuviae. This study aims to reveal if the lysosomal metal containing granules store calcium originating from the ingested exuviae. Therefore, we investigated the effect of cuticle ingestion on the elemental composition of the hepatopancreas granules of P. scaber, using electron probe X-ray microanalysis. For the preservation of diffusible elements, samples were high pressure frozen and freeze substituted in acetone and we used Propane-1,3-diol as a floatation medium for sections. We analyzed S- and B-cells of animals in the postmoult and intermoult stage that have ingested their exuviae and, as a negative control, cells from postmoult animals that have not ingested their exuviae. STEM and TEM were used for the investigation of the ultrastructure. Unexpectedly, the cryo-fixed samples contain numerous extracellular vesicles (exosomes) and many multivesicular bodies containing pro-exosomes. We show a significant increase of calcium, copper, zinc and sulphur within the metal granules upon exuviae ingestion, and, after 9â¯days, a reduction of calcium and zinc. The results indicate transitory storage of calcium from the exuviae within the metal granules and its subsequent utilization in cuticle mineralization.
Asunto(s)
Calcio/metabolismo , Exosomas/metabolismo , Hepatopáncreas/citología , Isópodos/metabolismo , Lisosomas/metabolismo , Animales , Cobre/metabolismo , Criopreservación , Hepatopáncreas/metabolismo , Hepatopáncreas/ultraestructura , Isópodos/citología , Fósforo/metabolismo , Azufre , Zinc/metabolismoRESUMEN
The hyperiidean amphipod Brachyscelus rapacoides Stephensen, 1925 is recorded from the scyphozoan jellyfish Rhopilema nomadica Galil, 1990, a new record of association for the genus Brachyscelus, as well as the first record of hyperiid infestation of a non-indigenous scyphozoan host. Because of some past confusion concerning the status of B. rapacoides and the closely related species B. rapax (Claus, 1871) a redescription of B. rapacoides and molecular analysis are provided in order to validate it as a species distinguished from B. rapax.
Asunto(s)
Anfípodos , Escifozoos , Animales , Mar MediterráneoRESUMEN
A new species of Pseudione Kossmann, 1881 is described from two parasitized specimens of the clawed lobster Nephropsis aculeata Smith, 1881, collected from Brazilian waters in the southwestern Atlantic. It is the second species of the genus from Brazil and is the fourth species parasitizing nephropid lobsters in the world.
Asunto(s)
Isópodos , Nephropidae , Animales , BrasilRESUMEN
Phenological mismatch-maladaptive changes in phenology resulting from altered timing of environmental cues-is an increasing concern in many ecological systems, yet its effects on disease are poorly characterized. American lobster (Homarus americanus) is declining at its southern geographic limit. Rising seawater temperatures are associated with seasonal outbreaks of epizootic shell disease (ESD), which peaks in prevalence in the fall. We used a 34-year mark-recapture data set to investigate relationships between temperature, molting phenology, and ESD in Long Island Sound, where temperatures are increasing at 0.4°C per decade. Our analyses support the hypothesis that phenological mismatch is linked to the epidemiology of ESD. Warming spring temperatures are correlated with earlier spring molting. Lobsters lose diseased cuticle by molting, and early molting increases the intermolt period in the summer, when disease prevalence is increasing to a fall peak. In juvenile and adult male lobsters, September ESD prevalence was correlated with early molting, while October ESD prevalence was correlated with summer seawater temperature. This suggests that temperature-induced molting phenology affects the timing of the onset of ESD, but later in the summer this signal is swamped by the stronger signal of summer temperatures, which we hypothesize are associated with an increased rate of new infections. October ESD prevalence was â¼80% in years with hot summers and â¼30% in years with cooler summers. Yearly survival of diseased lobsters is <50% that of healthy lobsters. Thus, population impacts of ESD are expected to increase with increasing seawater temperatures.
Asunto(s)
Muda , Nephropidae/fisiología , Exoesqueleto/crecimiento & desarrollo , Exoesqueleto/microbiología , Exoesqueleto/patología , Animales , Océano Atlántico , Infecciones Bacterianas/epidemiología , Nephropidae/crecimiento & desarrollo , Nephropidae/microbiología , Estaciones del Año , TemperaturaRESUMEN
The American lobster, Homarus americanus, is a model for investigating the neuromodulatory control of physiology and behavior. Prior studies have shown that multiple classes of chemicals serve as locally released/circulating neuromodulators/neurotransmitters in this species. Interestingly, while many neuroactive compounds are known from Homarus, little work has focused on identifying/characterizing the enzymes responsible for their biosynthesis, despite the fact that these enzymes are key components for regulating neuromodulation/neurotransmission. Here, an eyestalk ganglia-specific transcriptome was mined for transcripts encoding enzymes involved in neuropeptide, amine, diffusible gas and small molecule transmitter biosynthesis. Using known Drosophila melanogaster proteins as templates, transcripts encoding putative Homarus homologs of peptide precursor processing (signal peptide peptidase, prohormone processing protease and carboxypeptidase) and immature peptide modifying (glutaminyl cyclase, tyrosylprotein sulfotransferase, protein disulfide isomerase, peptidylglycine-α-hydroxylating monooxygenase and peptidyl-α-hydroxyglycine-α-amidating lyase) enzymes were identified in the eyestalk assembly. Similarly, transcripts encoding full complements of the enzymes responsible for dopamine [tryptophan-phenylalanine hydroxylase (TPH), tyrosine hydroxylase and DOPA decarboxylase (DDC)], octopamine (TPH, tyrosine decarboxylase and tyramine ß-hydroxylase), serotonin (TPH or tryptophan hydroxylase and DDC) and histamine (histidine decarboxylase) biosynthesis were identified from the eyestalk ganglia, as were those responsible for the generation of the gases nitric oxide (nitric oxide synthase) and carbon monoxide (heme oxygenase), and the small molecule transmitters acetylcholine (choline acetyltransferase), glutamate (glutaminase) and GABA (glutamic acid decarboxylase). The presence and identity of the transcriptome-derived transcripts were confirmed using RT-PCR. The data presented here provide a foundation for future gene-based studies of neuromodulatory control at the level of neurotransmitter/modulator biosynthesis in Homarus.
Asunto(s)
Aminas/metabolismo , Enzimas/análisis , Nephropidae/enzimología , Neuropéptidos/biosíntesis , Neurotransmisores/biosíntesis , Animales , Ganglios de InvertebradosRESUMEN
Whether cardiac output in decapod crustaceans is under circadian control has long been debated, with mixed evidence for and against the hypothesis. Moreover, the locus of the clock system controlling cardiac activity, if it is under circadian control, is unknown. However, a report that the crayfish heart in organ culture maintains a circadian oscillation in heartbeat frequency suggests the presence of a peripheral pacemaker within the cardiac neuromuscular system itself. Because the decapod heart is neurogenic, with contractions controlled by the five motor and four premotor neurons that make up the cardiac ganglion (CG), a likely locus for a circadian clock is the CG itself. Here, a CG-specific transcriptome was generated for the lobster, Homarus americanus, and was used to assess the presence/absence of transcripts encoding putative clock-related proteins in the ganglion. Using known Homarus brain/eyestalk ganglia clock-related proteins as queries, BLAST searches of the CG transcriptome were conducted for the five proteins that form the core clock, i.e., clock, cryptochrome 2, cycle, period and timeless, as well as for a variety of clock-associated, clock input pathway and clock output pathway proteins. With the exception of pigment dispersing hormone receptor [PDHR], a putative clock output pathway protein, one or more transcripts encoding each of the proteins searched for were identified from the CG assembly; no PDHR-encoding transcripts were found. RT-PCR confirmed the expression of all core clock transcripts in multiple independent CG cDNAs; RNA-Seq data suggest that both the motor and premotor neurons could contribute to the cellular locus of a pacemaker. These data provide support for the possible existence of an intrinsic circadian clock in the H. americanus CG, and form a foundation for guiding future anatomical, molecular and physiological investigations of circadian signaling in the lobster cardiac neuromuscular system.
Asunto(s)
Relojes Circadianos/genética , Nephropidae/genética , Animales , Proteínas CLOCK/genética , Ganglios/fisiología , Nephropidae/fisiología , TranscriptomaRESUMEN
Essentially all organisms exhibit recurring patterns of physiology/behavior that oscillate with a period of ~24-h and are synchronized to the solar day. Crustaceans are no exception, with robust circadian rhythms having been documented in many members of this arthropod subphylum. However, little is known about the molecular underpinnings of their circadian rhythmicity. Moreover, the location of the crustacean central clock has not been firmly established, although both the brain and eyestalk ganglia have been hypothesized as loci. The American lobster, Homarus americanus, is known to exhibit multiple circadian rhythms, and immunodetection data suggest that its central clock is located within the eyestalk ganglia rather than in the brain. Here, brain- and eyestalk ganglia-specific transcriptomes were generated and used to assess the presence/absence of transcripts encoding the commonly recognized protein components of arthropod circadian signaling systems in these two regions of the lobster central nervous system. Transcripts encoding putative homologs of the core clock proteins clock, cryptochrome 2, cycle, period and timeless were found in both the brain and eyestalk ganglia assemblies, as were transcripts encoding similar complements of putative clock-associated, clock input pathway and clock output pathway proteins. The presence and identity of transcripts encoding core clock proteins in both regions were confirmed using PCR. These findings suggest that both the brain and eyestalk ganglia possess all of the molecular components needed for the establishment of a circadian signaling system. Whether the brain and eyestalk clocks are independent of one another or represent a single timekeeping system remains to be determined. Interestingly, while most of the proteins deduced from the identified transcripts are shared by both the brain and eyestalk ganglia, assembly-specific isoforms were also identified, e.g., several period variants, suggesting the possibility of region-specific variation in clock function, especially if the brain and eyestalk clocks represent independent oscillators.
Asunto(s)
Encéfalo/fisiología , Proteínas CLOCK/fisiología , Ritmo Circadiano/fisiología , Ganglios/fisiología , Nephropidae/fisiología , Transcriptoma , Secuencia de Aminoácidos , Animales , Proteínas de Artrópodos/fisiología , Alineación de SecuenciaRESUMEN
The crustacean stomatogastric nervous system (STNS) is a well-known model for investigating neuropeptidergic control of rhythmic behavior. Among the peptides known to modulate the STNS are the C-type allatostatins (AST-Cs). In the lobster, Homarus americanus, three AST-Cs are known. Two of these, pQIRYHQCYFNPISCF (AST-C I) and GNGDGRLYWRCYFNAVSCF (AST-C III), have non-amidated C-termini, while the third, SYWKQCAFNAVSCFamide (AST-C II), is C-terminally amidated. Here, antibodies were generated against one of the non-amidated peptides (AST-C I) and against the amidated isoform (AST-C II). Specificity tests show that the AST-C I antibody cross-reacts with both AST-C I and AST-C III, but not AST-C II; the AST-C II antibody does not cross-react with either non-amidated peptide. Wholemount immunohistochemistry shows that both subclasses (non-amidated and amidated) of AST-C are distributed throughout the lobster STNS. Specifically, the antibody that cross-reacts with the two non-amidated peptides labels neuropil in the CoGs and the stomatogastric ganglion (STG), axons in the superior esophageal (son) and stomatogastric (stn) nerves, and ~ 14 somata in each commissural ganglion (CoG). The AST-C II-specific antibody labels neuropil in the CoGs, STG and at the junction of the sons and stn, axons in the sons and stn, ~ 42 somata in each CoG, and two somata in the STG. Double immunolabeling shows that, except for one soma in each CoG, the non-amidated and amidated peptides are present in distinct sets of neuronal profiles. The differential distributions of the two AST-C subclasses suggest that the two peptide groups are likely to serve different modulatory roles in the lobster STNS.
Asunto(s)
Sistema Digestivo/citología , Sistema Digestivo/inervación , Ganglios de Invertebrados/metabolismo , Neuropéptidos/metabolismo , Animales , Nephropidae/anatomía & histologíaRESUMEN
A new species of slipper lobster of the genus Petrarctus Holthuis, 2002 was discovered from southwestern India during a survey of deep sea crustaceans. The new species closely resembles P. veliger Holthuis, 2002 from the Andaman Sea and western Pacific but differs mainly in the color marking on abdominal somite I, having a relatively lower cardiac tooth but with better developed tubercles on the abdomen, as well as a differently shaped anterior part of the thoracic sternum. Molecular genetic analysis also confirms the distinct taxonomic status of the new species. To fix the identity of the type species of the genus, a neotype of P. rugosus (H. Milne Edwards, 1837) was selected from a recently collected Indian specimen with color and genetic information.
Asunto(s)
Nephropidae , Distribución Animal , Animales , Color , Decápodos , IndiaRESUMEN
The present study evaluated the effects of exposure to different target pCO2 levels: control (C: 370µatm, pH=8.15) and ocean acidification (OA: 710µatm, pH=7.85) on development and biochemical responses related with oxidative stress and energy metabolism during the crustacean Homarus gammarus (L.) larval development, integrating different levels of biological organization. After hatching in the laboratory, larvae from the same female brood were exposed to the described conditions from hatching until reaching Stage III (last larval stage - 11days). H. gammarus larvae demonstrated some susceptibility when addressing the predicted pCO2 levels for 2100. Further analysis at the biochemical and physiological level highlighted the occurrence of oxidative stress in the OA scenario (Superoxide Dismutase reduction and higher DNA damage) that was followed by developmental effects, increased inter-moult period from SII to SIII and reduced growth. The extended exposure to these conditions may affect organisms' key life-cycle functions such as physiological resistance, growth, sexual maturation, or reproduction with implications in their future fitness and population dynamics.
Asunto(s)
Dióxido de Carbono/toxicidad , Nephropidae/efectos de los fármacos , Agua de Mar/química , Animales , Biomarcadores , Metabolismo Energético/efectos de los fármacos , Metabolismo Energético/fisiología , Concentración de Iones de Hidrógeno , Larva/crecimiento & desarrollo , Muda , Nephropidae/crecimiento & desarrollo , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiologíaRESUMEN
The genus Fennerogalathea Baba, 1988 was known to contain two species: F. chacei Baba, 1988, the type species, from the Philippines, Taiwan and Indonesia and F. chirostyloides Tirmizi & Javed, 1993 from the Bay of Bengal. In the present study, three new species of the genus are described and illustrated: F. chani n. sp. from Papua New Guinea, F. cultrata n. sp. from New Caledonia and Vanuatu and F. ensifera n. sp. from Fiji. The new species are morphologically distinguishable on the basis of the shape and spination of the rostrum and the presence/absence of a small spine on the frontal margin of the carapace. The species also show clear genetic differences (COI and 16S rDNA) among them.
Asunto(s)
Nephropidae , Animales , Fiji , Indonesia , Nueva Caledonia , Océano Pacífico , Papúa Nueva Guinea , Filipinas , Taiwán , VanuatuRESUMEN
BACKGROUND: Neurotrophic factors such as nerve growth factor (NGF) play important roles in nervous system. NGF is a potential therapeutic drug for treatment of neurodegenerative diseases. However, because of physicochemical property, NGF cannot pass through the blood-brain barrier (BBB). Hence, small molecules which exhibit NGF-mimic activity and can pass through the BBB are considered to be promising drug candidates for treatment of such diseases. PURPOSE: The present study was designed to isolate NGF-mimic substance from extract of natural products, determine their structures and investigate mechanism of action of the active substance. METHODS: Extract of Lindernia crustacean was partitioned between water and ethyl acetate to obtain water layer and ethyl acetate layer samples, respectively, and then evaluated their neuritogenic activity in PC12 cells. The active sample was separated by open columns, followed by HPLC purification to obtain active compound. Then, specific inhibitors were used to investigate signaling pathway of neurite outgrowth induced by the active compound. Finally, western blot analysis was performed to confirm the pathway proposed by inhibitor experiments. RESULTS: The ethyl acetate layer sample of extract of Lindernia crustacea exhibited significant neuritogenic activity. Two new compounds, named as linderside A and lindersin B, were isolated; their structures were elucidated by spectroscopic and chemical derivatization methods. Linderside A is a cucurbitane glycoside, whereas lindersin B is a cucurbitane triterpenoid. Each compound has an unusual isopentene unit, namely, a double bond bound to an unmodified isopropyl group at the end of cucurbitane triterpenoid side chain. Among them, lindersin B induced significant neurite outgrowth in PC12 cells, while linderside A was inactive against PC12 cells. Western blotting analysis results showed that lindersin B-induced neuritogenic activity depended on the activation of the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK). Moreover, tyrosine kinase A (TrKA) and phosphatidylinositol 3 kinase (PI3K) were also involved in the signaling pathway. CONCLUSIONS: Two new cucurbitane triterpenoids, linderside A and lindersin B, were isolated from Lindernia crustacean. Neurite outgrowth induced by lindersin B in PC12 cells depends on activation of TrkA/PI3K/ERK signaling pathway.
Asunto(s)
Factores de Crecimiento Nervioso/uso terapéutico , Enfermedades Neurodegenerativas/tratamiento farmacológico , Fosfatidilinositol 3-Quinasas/metabolismo , Extractos Vegetales/uso terapéutico , Proteínas Tirosina Quinasas/metabolismo , Scrophulariaceae/química , Animales , China , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Células PC12/efectos de los fármacos , Fitoterapia , Extractos Vegetales/farmacología , Hojas de la Planta/química , Tallos de la Planta/química , Ratas , Transducción de Señal/efectos de los fármacosRESUMEN
In silico transcriptome mining is a powerful tool for crustacean peptidome prediction. Using homology-based BLAST searches and a simple bioinformatics workflow, large peptidomes have recently been predicted for a variety of crustaceans, including the lobster, Homarus americanus. Interestingly, no in silico studies have been conducted on the eyestalk ganglia (lamina ganglionaris, medulla externa, medulla interna and medulla terminalis) of the lobster, although the eyestalk is the location of a major neuroendocrine complex, i.e., the X-organ-sinus gland system. Here, an H. americanus eyestalk ganglia-specific transcriptome was produced using the de novo assembler Trinity. This transcriptome was generated from 130,973,220 Illumina reads and consists of 147,542 unique contigs. Eighty-nine neuropeptide-encoding transcripts were identified from this dataset, allowing for the deduction of 62 distinct pre/preprohormones. Two hundred sixty-two neuropeptides were predicted from this set of precursors; the peptides include members of the adipokinetic hormone-corazonin-like peptide, allatostatin A, allatostatin B, allatostatin C, bursicon α, CCHamide, corazonin, crustacean cardioactive peptide, crustacean hyperglycemic hormone (CHH), CHH precursor-related peptide, diuretic hormone 31, diuretic hormone 44, eclosion hormone, elevenin, FMRFamide-like peptide, glycoprotein hormone α2, glycoprotein hormone ß5, GSEFLamide, intocin, leucokinin, molt-inhibiting hormone, myosuppressin, neuroparsin, neuropeptide F, orcokinin, orcomyotropin, pigment dispersing hormone, proctolin, pyrokinin, red pigment concentrating hormone, RYamide, short neuropeptide F, SIFamide, sulfakinin, tachykinin-related peptide and trissin families. The predicted peptides expand the H. americanus eyestalk ganglia neuropeptidome approximately 7-fold, and include 78 peptides new to the lobster. The transcriptome and predicted neuropeptidome described here provide new resources for investigating peptidergic signaling within/from the lobster eyestalk ganglia.
Asunto(s)
Biología Computacional/métodos , Ojo/metabolismo , Ganglios/metabolismo , Nephropidae/genética , Proteínas del Tejido Nervioso/genética , Neuropéptidos/análisis , Transcriptoma , Secuencia de Aminoácidos , Animales , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/metabolismo , Ojo/crecimiento & desarrollo , Ganglios/crecimiento & desarrollo , Nephropidae/crecimiento & desarrollo , Nephropidae/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteoma/análisis , Homología de Secuencia de AminoácidoRESUMEN
The Galapagos slipper lobster Scyllarides astori was found for the first time off western Mexico mainland. A male and two female specimens were collected in south Jalisco and north Colima. This represents a new record from central Pacific coast of Mexico and a range extension of 700 km southwards, as the species was previously reported from the Gulf of California, 780 km eastwards from Revillagigedo Archipelago and 2400 km northwestwards from Isla del Coco and Galapagos Archipelago.
Asunto(s)
Nephropidae , Animales , California , Femenino , Masculino , Océano PacíficoRESUMEN
Herein, we report the response of indices based on phytoplankton and zooplankton and their combination to different nutrient concentrations in lakes. The study was carried out in ten lakes in northeastern Poland. Integrated samples were collected from the epilimnion during the summer of 2012-2013. Secchi disk visibility (SD), total phosphorus (TP), total nitrogen (TN), and chlorophyll a were used as proxies for eutrophication. We calculated 16 plankton indices: two phytoplankton indices, six crustacean indices, five rotiferan indices, two zooplankton diversity indices, and one combined phytoplankton and zooplankton index. Among them, nine indices with the strongest correlations with TP were selected: percentage share of Crustacean species indicative of high trophy in the indicative group's numbers (IHTCRU), percentage share of Rotifera species indicative of high trophy in the indicative group's numbers IHTROT, Crustacean ratio of biomass to numbers B/NCRU, phytoplankton trophic index (TITP+TN), Margalef's index, percentage share of cyclopoid biomass in total biomass of Crustacea (CB), Rotifera numbers (NROT), biomass of Cyclopoida (BCY), and ratio of the cyclopoid biomass to the biomass of Cladocera (CY/CL). The sensitivity of the normalized values of these indices to proxies of eutrophication was tested. IHTCRU, IHTROT, and B/NCRU were the most sensitive and gave the strongest responses at lower TP concentrations (<35 µg/L). The phytoplankton trophic index, TITP+TN, together with the zooplankton-based Margalef's index and CB were very sensitive in both low (<35 µg/L) and high (>60 µg/L) TP conditions. On the other hand, NROT, BCY, and CY/CL were slightly sensitive at low TP concentrations while their reaction was notable at high TP concentrations. A similar pattern of response was observed for TN concentration and SD visibility.