RESUMEN
Domoic acid (DA) is a dangerous phycotoxin produced by several strains of diatoms of the genus Pseudo-nitzschia, and responsible for Amnesic Shellfish Poisoning (ASP) in humans. The increasingly intense ASP-outbreaks along the English Channel over the last three decades have forced persistent harvest closures of economically important and highly contaminated bivalve stocks exhibiting slow DA-depuration rates, like the king scallop Pecten maximus. Under this scenario, other pectinid species, such as the queen scallop Aequipecten opercularis have been empirically proposed as alternative resources to redress the high economic losses due to the banning of the exploitation of P. maximus. Nevertheless, the kinetics of DA depuration in A. opercularis have not been assessed so far, and its direct extraction after ASP-episodes could represent a serious threat to public health. Hence, the main objective of this work was to estimate the DA-depuration rate in the digestive gland (DG) of naturally contaminated scallops A. opercularis after a toxic Pseudo-nitzschia australis bloom subjected to experimental depuration in the laboratory for 30 days. This study also intended to go further in the knowledge about the anatomical distribution of DA in scallop tissues, and corroborate the implications of autophagy in DA-sequestration in the DG of this species as recently hypothesized. In the DG, the DA-depuration rate (0.018 day-1) suggested that even with toxin burdens as low as 40 mgâ kg-1 in the DG, queen scallops may remain contaminated for about 70 days, thus longer under intensely contamination scenarios. The subcellular analyses corroborated DA-sequestration mainly through late-autophagy within residual bodies in the DG, without differences in the frequencies of anti-DA labeled residual bodies across the entire depuration process. These results revealed that A. opercularis cannot be considered a fast DA-depurator, and represent a baseline knowledge for decision-making about harvesting natural beds of queen scallops after toxic Pseudo-nitzschia blooms. The findings of this work also represent a cornerstone for further research to accelerate DA-depuration in this species.
Asunto(s)
Ácido Kaínico , Pectinidae , Ácido Kaínico/análogos & derivados , Ácido Kaínico/metabolismo , Pectinidae/fisiología , Animales , Toxinas Marinas/análisis , Toxinas Marinas/metabolismo , Diatomeas/fisiología , Diatomeas/metabolismo , Intoxicación por Mariscos , Floraciones de Algas NocivasRESUMEN
The bay scallop, Argopecten irradians, is a species of major commercial, cultural, and ecological importance. It is endemic to the eastern coast of the United States, but has also been introduced to China, where it supports a significant aquaculture industry. Here, we provide an annotated chromosome-level reference genome assembly for the bay scallop, assembled using PacBio and Hi-C data. The total genome size is 845.9 Mb, distributed over 1,503 scaffolds with a scaffold N50 of 44.3 Mb. The majority (92.9%) of the assembled genome is contained within the 16 largest scaffolds, corresponding to the 16 chromosomes confirmed by Hi-C analysis. The assembly also includes the complete mitochondrial genome. Approximately 36.2% of the genome consists of repetitive elements. The BUSCO analysis showed a completeness of 96.2%. We identified 33,772 protein-coding genes. This genome assembly will be a valuable resource for future research on evolutionary dynamics, adaptive mechanisms, and will support genome-assisted breeding, contributing to the conservation and management of this iconic species in the face of environmental and pathogenic challenges.
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Cromosomas , Genoma , Pectinidae , Pectinidae/genética , Animales , Genoma MitocondrialRESUMEN
Objective: Daiwa Brain Health, which contains Hokkaido scallop oil plasmalogen, was compared with Prevagen, the market leader in the category of cognitive function improvement. Methods: Thirty people with subjective cognitive decline or its premorbidities were divided into 2 groups of 15 people each, and each group was given either Daiwa Brain Health or Prevagen for 90 days. The Abbreviated Mental Test Score (AMTS) and Standardized Mini-Mental State Examination (SMMSE) were conducted before treatment and after 90 days of treatment to evaluate cognitive function. Results: Participants who took Daiwa Brain Health showed statistically significant improvement in AMTS and SMMSE scores between baseline and 90 days of treatment, while participants who took Prevagen showed no statistically significant improvement in AMTS or SMMSE scores between baseline and after 90 days of treatment. The AMTS and SMMSE scores indicated higher cognitive function at 90 days after treatment for the participants who took Daiwa Brain Health compared with those who took Prevagen, and those differences were statistically significant. Conclusion: Daiwa Brain Health is more effective than Prevagen at improving cognitive function.
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Cognición , Humanos , Proyectos Piloto , Masculino , Femenino , Cognición/efectos de los fármacos , Anciano , Persona de Mediana Edad , Disfunción Cognitiva , Pectinidae , Anciano de 80 o más AñosRESUMEN
Scallop oil (SCO) prepared from the internal organs of the Japanese giant scallop (Patinopecten yessoensis) contains eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and phospholipids (PL). It was previously shown that SCO consumption improves cholesterol and triacylglycerols (TG) contents in mice. The present study demonstrated the effects of daily SCO consumption (1.2 g/day, containing 376 mg of EPA, 63 mg of DHA, and 150 mg of PL) for 12 weeks in human subjects. In this randomized, doubleblind, placebo-controlled, parallel group comparison study, 70 Japanese subjects with serum TG levels ≥120 but < 200 mg/dL were recruited and randomly assigned to the SCO or placebo group. All subjects ingested six capsules per day for 12 weeks. We conducted medical interviews, body composition measurements, vital sign examinations, and blood sampling at weeks 0 (baseline), 4, 8, and 12, and measured peripheral blood flow at weeks 0 and 12. In the case of subjects with higher serum TG levels, SCO consumption decreased the changes in serum TG and malondialdehyde-low density lipoprotein (MDA-LDL) levels compared with the placebo group. Safety assessment revealed no medically significant changes due to continuous SCO consumption. The findings indicate that 1.2 g/day of SCO consumption may be beneficial for reducing serum TG and MDA-LDL levels in persons with higher TG levels.
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Ácido Eicosapentaenoico , Pectinidae , Triglicéridos , Adulto , Anciano , Animales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ácidos Docosahexaenoicos/administración & dosificación , Método Doble Ciego , Pueblos del Este de Asia , Ácido Eicosapentaenoico/administración & dosificación , Lípidos/sangre , Malondialdehído/sangre , Aceites/química , Pectinidae/química , Fosfolípidos , Triglicéridos/sangreRESUMEN
Mitogen-activated protein kinase kinase (MKK), the key element of the Mitogen-activated protein kinase (MAPK) signaling pathway, is crucial for the immune response to adverse environments in aquatic animals. Nevertheless, there is limited information regarding the role of the MKK gene family in mollusks. In our study, genome data and transcriptome were used to identify four MKK genes (CnMKK4, CnMKK5, CnMKK6, and CnMKK7) in the noble scallop. The result of the gene structure, motif analysis, and phylogenetic tree revealed that MKK genes are relatively conserved in bivalves. Moreover, four CnMKK genes were significantly highly expressed in immune-related tissues, suggesting that CnMKKs may related to bivalve immunity. Furthermore, CnMKK6 and CgMKK4 were significantly differentially expressed (P < 0.05) under 24 h of temperature stress, and all CnMKKs were significantly differentially expressed (P < 0.05) under 24 h of Vibrio parahaemolyticus infection. These results showed that the CnMKKs may have a significant impact under biotic and abiotic stresses. In conclusion, the result of the CnMKKs provides valuable insights into comprehending the function of MKK genes in mollusks.
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Pectinidae , Filogenia , Estrés Fisiológico , Vibrio parahaemolyticus , Animales , Pectinidae/genética , Pectinidae/microbiología , Pectinidae/inmunología , Pectinidae/fisiología , Vibrio parahaemolyticus/fisiología , Estrés Fisiológico/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , TemperaturaRESUMEN
A global increase in offshore windfarm development is critical to our renewable energy future. Yet, widespread construction plans have generated substantial concern for impacts to co-occurring organisms and the communities they form. Pile driving construction, prominent in offshore windfarm development, produces among the highest amplitude sounds in the ocean creating widespread concern for a diverse array of taxa. However, studies addressing ecologically key species are generally lacking and most research is disparate, failing to integrate across response types (e.g., behavior, physiology, and ecological interactions), particularly in situ. The lack of integrative field studies presents major challenges to understand or mitigate actual impacts of offshore wind development. Here, we examined critical behavioral, physiological, and antipredator impacts of actual pile driving construction on the giant sea scallop (Placopecten magellanicus). Benthic taxa including bivalves are of particular concern because they are sound-sensitive, cannot move appreciable distances away from the stressor, and support livelihoods as one of the world's most economically and socially important fisheries. Overall, pile driving sound impacted scallops across a series of behavioral and physiological assays. Sound-exposed scallops consistently reduced their valve opening (22%), resulting in lowered mantle water oxygen levels available to the gills. Repeated and rapid valve adductions led to a 56% increase in metabolic rates relative to pre-exposure baselines. Consequently, in response to predator stimuli, sound-exposed scallops displayed a suite of significantly weaker antipredator behaviors including fewer swimming events and shorter time-to-exhaustion. These results show aquatic construction activities can induce metabolic and ecologically relevant changes in a key benthic animal. As offshore windfarm construction accelerates globally, our field-based study highlights that spatial overlap with benthic taxa may cause substantial metabolic changes, alter important fisheries resources, and ultimately could lead to increased predation.
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Viento , Animales , Organismos Acuáticos/fisiología , Pectinidae/fisiología , Pectinidae/metabolismo , Conducta Predatoria , Cadena AlimentariaRESUMEN
The mariculture industry has seen a rapid expansion in recent years due to the increasing global demand for seafood. However, the industry faces challenges from climate change and increased pathogen pressure. Additionally, the chemicals used to enhance mariculture productivity are changing ocean ecosystems. This study analyzed 36 surface-water metagenomes from South Korean mussel, oyster, scallop, and shrimp farms to expand our understanding of aquaculture microbial genetic resources and the potential impacts of these anthropogenic inputs. We recovered 240 non-redundant species-level metagenome-assembled genomes (MAGs), comprising 224 bacteria, 13 archaea, and three eukaryotes. Most MAGs were assigned to Proteobacteria, Bacteroidota, and Actinobacteriota, with 40.7% remaining unclassified at the species level. Among the three eukaryotic MAGs, one was identified as a novel lineage of green algae, highlighting the uncharacterized genetic diversity in mariculture environments. Additionally, 22 prokaryotic MAGs harbored 26 antibiotic and metal resistance genes, with MAGs carrying beta-lactamases being particularly prevalent in most farms. The obtained microbiome data from mariculture environments can be utilized in future studies to foster healthy, sustainable mariculture practices.
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Acuicultura , Metagenoma , República de Corea , Animales , Bacterias/genética , Bacterias/clasificación , Microbiota , Ostreidae/microbiología , Archaea/genética , Pectinidae/microbiología , Pectinidae/genética , Penaeidae/microbiología , Penaeidae/genéticaRESUMEN
The Ylistrum japonicum is a commercially valuable scallop known for its long-distance swimming abilities. Despite its economic importance, genetic and genomic research on this species is limited. This study presents the first complete mitochondrial genome of Y. japonicum. The mitochondrial genome is 19,475 bp long and encompasses 13 protein-coding genes, three ribosomal RNA genes, and 23 transfer RNA genes. Two distinct phylogenetic analyses were used to explore the phylogenetic position of the Y. japonicum within the family Pectinidae. Based on one mitochondrial phylogenetic analysis by selecting 15 Pectinidae species and additional outgroup taxa and one single gene phylogenetic analysis by 16S rRNA, two phylogenetic trees were constructed to provide clearer insights into the evolutionary placement of Y. japonicum within the family Pectinidae. Our analysis reveals that Ylistrum is a basal lineage to the Pectininae clade, distinct from its previously assigned tribe, Amusiini. This study offers critical insights into the genetic makeup and evolutionary history of Y. japonicum, enhancing our knowledge of this economically vital species.
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Genoma Mitocondrial , Pectinidae , Filogenia , Animales , Genoma Mitocondrial/genética , Pectinidae/genética , Pectinidae/clasificación , ARN Ribosómico 16S/genética , ARN de Transferencia/genética , Evolución MolecularRESUMEN
In this study, the effects of ultrasound combined with ferulic acid (FA) on the quality of the Yesso scallop (Patinopecten yessoensis) adductor muscles (SAM) during refrigerated storage were investigated. The results demonstrated that the combined treatment with 350 W ultrasound and FA (UFA) significantly delayed enzyme activities and microbial growth in SAM tissues compared to FA treatment alone. After 6 days of cold storage, samples treated with UFA exhibited higher hardness (2850 g), lower thiobarbituric acid reactive substances (TBARS = 9.35 MDA mg/g SAM), and lower total volatile basic nitrogen (TVB-N = 19.75 mg/100 g SAM) values compared to control and FA-treated samples. Consequently, UFA treatment prolonged the shelf life of SAM by 3 days during storage at 4°C. Based on scanning electron microscopy and low-field nuclear magnetic resonance data, these findings are attributed to UFA treatment not only reducing the degradation of SAM tissue network structure but also minimizing water loss. PRACTICAL APPLICATION: Scallop adductor muscle (SAM) is commonly considered a delicacy owing to its unique mouthfeel and delicious taste. However, owing to its high moisture content and high levels of various nutrients, SAM has a short shelf life. In this work, a combination of ultrasound with ferulic acid (UFA) has been found to have effective preservation effects on SAM during refrigerated storage. Our study findings pave the way for a potential approach to maintain scallop quality during processing and storage. Moreover, our study also provides some theoretical basis for using and promoting these technologies in aquatic products.
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Ácidos Cumáricos , Conservación de Alimentos , Pectinidae , Ácidos Cumáricos/análisis , Pectinidae/química , Animales , Conservación de Alimentos/métodos , Almacenamiento de Alimentos/métodos , Alimentos Marinos/análisis , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Manipulación de Alimentos/métodos , Ultrasonido/métodosRESUMEN
In bivalve, development of female gonad is accompanied with accumulating lipids which provided energy resource for non-feeding larvae development. As the major transcriptional regulators of lipid metabolism, Srebps play pivotal role in lipid homeostasis during oogenesis. However, little work was conducted on Srebps function in bivalves. The noble scallop Chlamys nobilis accumulated large amount of lipids in its gonad during oogenesis. Here, we identified a single Srebp gene (named Srebp-1) with a high similarity to human Srebp-1c. Disrupting Srebp-1 with Betulin (inhibiting the maturation of Srebp protein) repressed expression of lipogenic genes and de novo lipogenesis, and resulted in reduction of gonad index and lipid deposition, suggesting a crucial role of Srebp-1 for gonad development and lipid synthesis in female gonad. Additionally, scallops with Srebp-1 disruption released fewer eggs with a reduction in their lipid content and D-larvae formation, revealing an impair of fecundity caused by Srebp-1 disruption. Cold exposure stimulated lipid accumulation which required Srebp-1 to regulate de novo lipogenesis and lipid uptake, providing a crosstalk of Srebp-1 activity and environmental variation on lipid accumulation in noble scallop. Thus, our study identified Srebp-1 as a central regulator coordinating the lipid synthesis and accumulation with gonad development in noble scallop.
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Gónadas , Lipogénesis , Pectinidae , Proteína 1 de Unión a los Elementos Reguladores de Esteroles , Animales , Pectinidae/metabolismo , Pectinidae/crecimiento & desarrollo , Pectinidae/genética , Lipogénesis/genética , Gónadas/metabolismo , Gónadas/crecimiento & desarrollo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Femenino , Metabolismo de los Lípidos , Oogénesis , Regulación del Desarrollo de la Expresión GénicaRESUMEN
Azaspiracids (AZAs) are lipid biotoxins produced by the marine dinoflagellates Azadinium and Amphidoma spp. that can accumulate in shellfish and cause food poisoning in humans. However, the mechanisms underlying the tolerance of shellfish to high levels of such toxins remain poorly understood. This study investigated the combined effects of detoxification metabolism and stress-related responses in scallops Chlamys farreri exposed to AZA. Scallops accumulated a maximum of 361.81 µg AZA1 eq/kg and 41.6 % AZA residue remained after 21 days of exposure. A range of AZA2 metabolites, including AZA19, AZA11, and AZA23, and trace levels of AZA2-GST, were detected. Total hemocyte counts significantly increased and ROS levels remained consistently high until gradually decreasing. Immune system activation mediated mitochondrial dysfunction and severe energy deficiency. DEGs increased over time, with key genes CYP2J6 and GPX6 contributing to AZA metabolism. These transcriptome and metabolic results identify the regulation of energy metabolism pathways, including inhibition of the TCA cycle and activation of carbohydrates, amino acids, and lipids. AZA also induced autophagy through the MAPK-AMPK signaling pathways, and primary inhibited PI3K/AKT to decrease mTOR pathway expression. Our results provide additional insights into the resistance of C. farreri to AZA, characterized by re-establishing redox homeostasis toward a more oxidative state.
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Toxinas Marinas , Pectinidae , Compuestos de Espiro , Animales , Toxinas Marinas/toxicidad , Compuestos de Espiro/toxicidad , Pectinidae/efectos de los fármacos , Pectinidae/metabolismo , Pectinidae/inmunología , Especies Reactivas de Oxígeno/metabolismo , Metabolismo Energético/efectos de los fármacos , Transcriptoma/efectos de los fármacos , Toxinas PoliéteresRESUMEN
Calcium/calmodulin dependent protein kinase kinase (CaMKK), a highly conserved protein kinase, is involved in the downstream processes of various biological activities by phosphorylating and activating 5'-AMP-activated protein kinase (AMPK) in response to the increase of cytosolic-free calcium (Ca2+). In the present study, a CaMKKI was identified from Yesso scallop Patinopecten yessoensis. Its mRNA was ubiquitously expressed in haemocytes and all tested tissues with the highest expression level in mantle. The expression level of PyCaMKKI mRNA in adductor muscle was significantly upregulated at 1, 3 and 6 h after high temperature treatment (25 °C), which was 3.43-fold (p < 0.05), 5.25-fold (p < 0.05), and 5.70-fold (p < 0.05) of that in blank group, respectively. At 3 h after high temperature treatment (25 °C), the protein level of PyAMPKα, as well as the phosphorylation level of PyAMPKα at Thr170 in adductor muscle, and the positive co-localized fluorescence signals of PyCaMKKI and PyAMPKα in haemocyte all increased significantly (p < 0.05) compared to blank group (18 °C). The pull-down assay showed that rPyCaMKKI and rPyAMPKα could bind each other in vitro. After PyCaMKKI was silenced by siRNA, the mRNA and protein levels of PyCaMKKI and PyAMPKα, and the phosphorylation level of PyAMPKα at Thr170 in adductor muscle were significantly down-regulated (p < 0.05) compared with the negative control group receiving an injection of siRNA-NC. These results collectively suggested that PyCaMKKI was involved in the activation of PyAMPKα in response to high temperature stress and would be helpful for understanding the function of PyCaMKKI-PyAMPKα pathway in maintaining energy homeostasis under high temperature stress in scallops.
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Proteínas Quinasas Activadas por AMP , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina , Pectinidae , Animales , Pectinidae/inmunología , Pectinidae/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/metabolismo , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/genética , Fosforilación , Respuesta al Choque Térmico , Hemocitos/metabolismo , ARN Interferente Pequeño/genética , Calor , Estrés FisiológicoRESUMEN
Adenosine Deaminases Acting on RNA (ADARs) are evolutionarily conserved enzymes known to convert adenosine to inosine in double-stranded RNAs and participate in host-virus interactions. Conducting a meta-analysis of available transcriptome data, we identified and characterised eight ADAR transcripts in Chlamys farreri, a farmed marine scallop susceptible to Acute viral necrosis virus (AVNV) infections and mortality outbreaks. Accordingly, we identified six ADAR genes in the Zhikong scallop genome, revised previous gene annotations, and traced alternative splicing variants. In detail, each ADAR gene encodes a unique combination of functional domains, always including the Adenosine deaminase domain, RNA binding domains and, in one case, two copies of a Z-DNA binding domain. After phylogenetic analysis, five C. farreri ADARs clustered in the ADAR1 clade along with sequences from diverse animal phyla. Gene expression analysis indicated CF051320 as the most expressed ADAR, especially in the eye and male gonad. The other four ADAR1 genes and one ADAR2 gene exhibited variable expression levels, with CF105370 and CF051320 significantly increasing during early scallop development. ADAR-mediated single-base editing, evaluated across adult C. farreri tissues and developmental stages, was mainly detectable in intergenic regions (83 % and 85 %, respectively). Overall, the expression patterns of the six ADAR genes together with the editing and hyper-editing values computed on scallops RNA-seq samples support the adaptive value of ADAR1-mediated editing, particularly in the pre-settling larval stages.
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Adenosina Desaminasa , Pectinidae , Filogenia , Edición de ARN , Animales , Adenosina Desaminasa/genética , Adenosina Desaminasa/metabolismo , Pectinidae/genética , Pectinidae/inmunología , Inmunidad Innata/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/inmunología , Secuencia de Aminoácidos , Transcriptoma , Alineación de Secuencia/veterinariaRESUMEN
Fas-associated protein with death domain (FADD) was initially identified as a crucial adaptor protein in the apoptotic pathway mediated by death receptor (DR). Subsequently, many studies have confirmed that FADD plays a vital role in innate immunity and inflammatory responses in animals. However, the function of this pleiotropic molecule in mollusk species has not been well explored. In this study, we successfully verified the gene sequence of FADD in the Zhikong scallop (Chlamys farreri) and designated it as CfFADD. The CfFADD protein contains a conserved death effector and death domains. Phylogenetic analysis showed that CfFADD is a novel addition to the molluscan FADD family with a close evolutionary relationship with molluscan FADD subfamily proteins. CfFADD mRNA expression in various scallop tissues was significantly induced by challenge with pathogen-associated molecular patterns (lipopolysaccharide, peptidoglycan, and poly(I:C)), suggesting its role in innate immunity in scallops. Co-immunoprecipitation showed that CfFADD interacted with the scallop DR (tumor necrosis factor receptor) and a signaling molecule involved in the Toll-like receptor pathway (interleukin-1 receptor-associated kinase), confirming that CfFADD may be involved in DR-mediated apoptosis and innate immune signaling pathways. Further studies showed that CfFADD interacted with CfCaspase-8 and activated caspase-3. HEK293T cells exhibited distinct apoptotic features after transfection with a CfFADD-expression plasmid, suggesting a functional DR-FADD-caspase apoptotic pathway in scallops. Overexpression of CfFADD led to a significant dose-dependent activation of interferon ß and nuclear factor-κB reporter genes, demonstrating the key role of CfFADD in innate immunity. In summary, our research has confirmed the critical roles of CfFADD in innate immunity and apoptosis and provides valuable information for developing comparative immunology theories.
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Apoptosis , Proteína de Dominio de Muerte Asociada a Fas , Inmunidad Innata , Transducción de Señal , Animales , Humanos , Secuencia de Aminoácidos , Proteína de Dominio de Muerte Asociada a Fas/metabolismo , Proteína de Dominio de Muerte Asociada a Fas/genética , Regulación de la Expresión Génica , Moluscos/inmunología , Moluscos/genética , Pectinidae/inmunología , Pectinidae/genética , FilogeniaRESUMEN
Previous studies have shown that feeding mice with food containing mantle tissue from Japanese scallops results in aggravated liver and kidney damage, ultimately resulting in mortality within weeks. The aim of this study is to evaluate the toxicity of scallop mantle in China's coastal areas and explore the impact of scallop mantle toxins (SMT) on intestinal barrier integrity and gut microbiota in mice. The Illumina MiSeq sequencing of V3-V4 hypervariable regions of 16S ribosomal RNA was employed to study the alterations in gut microbiota in the feces of SMT mice. The results showed that intestinal flora abundance and diversity in the SMT group were decreased. Compared with the control group, significant increases were observed in serum indexes related to liver, intestine, inflammation, and kidney functions among SMT-exposed mice. Accompanied by varying degrees of tissue damage observed within these organs, the beneficial bacteria of Muribaculaceae and Marinifilaceae significantly reduced, while the harmful bacteria of Enterobacteriaceae and Helicobacter were significantly increased. Taken together, this article elucidates the inflammation and glucose metabolism disorder caused by scallop mantle toxin in mice from the angle of gut microbiota and metabolism. SMT can destroy the equilibrium of intestinal flora and damage the intestinal mucosal barrier, which leads to glucose metabolism disorder and intestinal dysfunction and may ultimately bring about systemic toxicity.
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Microbioma Gastrointestinal , Mucosa Intestinal , Pectinidae , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Pectinidae/microbiología , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/microbiología , Mucosa Intestinal/metabolismo , Ratones , Toxinas Marinas/toxicidad , Masculino , Bacterias/efectos de los fármacos , Bacterias/genética , Intestinos/microbiología , Intestinos/efectos de los fármacos , Heces/microbiología , ARN Ribosómico 16S/genética , Funcion de la Barrera IntestinalRESUMEN
Myofibrillar proteins (MPs) have a notable impact on the firmness and flexibility of gel-based products. Therefore, enhancing the gelation and emulsification properties of scallop MPs is of paramount significance for producing high-quality scallop surimi products. In this study, we investigated the effects of high-intensity ultrasound on the physicochemical and gelation properties of MPs from bay scallops (Argopecten irradians). The carbonyl content of MPs significantly increased with an increase in ultrasound power (150, 350, and 550 W), indicating ultrasound-induced MP oxidation. Meanwhile, high-intensity ultrasound treatment (550 W) enhanced the emulsifying capacity and the short-term stability of MPs (up to 72.05 m2/g and 153.05 min, respectively). As the ultrasound power increased, the disulfide bond content and surface hydrophobicity of MPs exhibited a notable increase, indicating conformational changes in MPs. Moreover, in the secondary structure of MPs, the α-helix content significantly decreased, whereas the ß-sheet content increased, thereby suggesting the ultrasound-induced stretching and flexibility of MP molecules. Sodium-dodecyl sulfate-polyacrylamide gel electrophoresis and scanning electron microscopy analysis further elucidated that high-intensity ultrasound induced MP oxidation, leading to modification of amino acid side chains, intra- and intermolecular cross-linking, and MP aggregation. Consequently, high-intensity ultrasound treatment was found to augment the viscoelasticity, gel strength, and water-holding capacity of MP gels, because ultrasound treatment facilitated the formation of a stable network structure in protein gels. Thus, this study offers theoretical insights into the functional modification of bay scallop MPs and the processing of its surimi products.
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Geles , Proteínas Musculares , Pectinidae , Pectinidae/química , Animales , Geles/química , Proteínas Musculares/química , Ondas Ultrasónicas , Fenómenos Químicos , Interacciones Hidrofóbicas e Hidrofílicas , Emulsiones/químicaRESUMEN
Myeloid differentiation factor-88 (MyD88) is a key adaptor of the toll-like receptor (TLR) signaling pathway and plays a crucial role in innate immune signal transduction in animals. However, the MyD88-mediated signal transduction mechanism in shellfish has not been well studied. In this study, a new MyD88 gene, CfMyD88-2, was identified in the Zhikong scallop, Chlamys farreri. The 1779 bp long open reading frame encodes 592 amino acids. The N-terminus of CfMyD88-2 contains a conserved death domain (DD), followed by a TIR (TLR/Interleukin-1 Receptor) domain. The results of the multi-sequence comparison showed that the TIR domain sequences were highly conserved. Phylogenetic analysis revealed that CfMyD88-2 was first associated with Mizuhopecten yessoensis MyD88-4 and Argopecten irradians MyD88-4. CfMyD88-2 mRNA was expressed in all scallop tissues, as detected by qRT-PCR, and the expression level was the highest in the mantle and hepatopancreas. In addition, CfMyD88-2 mRNA expression significantly increased after pathogen-associated molecular patterns (PAMPs, such as lipopolysaccharide, peptidoglycan, or polyinosinic-polycytidylic acid) stimulation. The results of the co-immunoprecipitation experiments in HEK293T cells showed that both CfMyD88-1 and CfMyD88-2 interacted with the TLR protein of scallops, suggesting the existence of more than one functional TLR-MyD88 signaling axis in scallops. Dual luciferase reporter gene assays indicated that the overexpressed CfMyD88-2 in HEK293T cells activated interferon (IFN) α, IFN-ß, IFN-γ, and NF-κB reporter genes, indicating that the protein has multiple functions. The results of the subcellular localization experiment uncovered that CfMyD88-2 was mainly localized in the cytoplasm of human cells. In summary, the novel identified CfMyD88-2 can respond to the challenge of PAMPs, participate in TLR immune signaling, and may activate downstream effector genes such as NF-κB gene. These research results will be useful in advancing the theory of innate immunity in invertebrates and provide a reference for the selection of disease-resistant scallops in the future.
Asunto(s)
Secuencia de Aminoácidos , Regulación de la Expresión Génica , Inmunidad Innata , Factor 88 de Diferenciación Mieloide , Pectinidae , Filogenia , Alineación de Secuencia , Receptores Toll-Like , Animales , Inmunidad Innata/genética , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/inmunología , Factor 88 de Diferenciación Mieloide/metabolismo , Pectinidae/inmunología , Pectinidae/genética , Receptores Toll-Like/genética , Receptores Toll-Like/inmunología , Receptores Toll-Like/química , Alineación de Secuencia/veterinaria , Regulación de la Expresión Génica/inmunología , Perfilación de la Expresión Génica/veterinaria , Transducción de Señal/inmunología , Humanos , Células HEK293 , Secuencia de BasesRESUMEN
The bay scallop is a eurythermal species with high economic value and now represents the most cultured bivalve species in China. Two subspecies of the bay scallop, the northern subspecies Argopecten irradians irradians Korean population (KK) and the southern subspecies Argopecten irradians concentricus (MM), exhibited distinct adaptations to heat stress. However, the molecular mechanism of heat resistance of the two subspecies remains unclear. In this study, we compared the transcriptomic responses of the two subspecies to heat stress and identified the involved differentially expressed genes (DEGs) and pathways. More DEGs were found in the KK than in the MM when exposed to high temperatures, indicating elevated sensitivity to thermal stress in the KK. Enrichment analysis suggests that KK scallops may respond to heat stress more swiftly by regulating GTPase activity. Meanwhile, MM scallops exhibited higher resistance to heat stress mainly by effective activation of their antioxidant system. Chaperone proteins may play different roles in responses to heat stress in the two subspecies. In both subspecies, the expression levels of antioxidants such as GST were significantly increased; the glycolysis process regulated by PC and PCK1 was greatly intensified; and both apoptotic and anti-apoptotic systems were significantly activated. The pathways related to protein translation and hydrolysis, oxidoreductase activity, organic acid metabolism, and cell apoptosis may also play pivotal roles in the responses to heat stress. The results of this study may provide a theoretical basis for marker-assisted breeding of heat-resistant strains.
Asunto(s)
Perfilación de la Expresión Génica , Pectinidae , Transcriptoma , Animales , Pectinidae/genética , Pectinidae/fisiología , Termotolerancia/genética , Respuesta al Choque TérmicoRESUMEN
Bivalves hold an important role in marine aquaculture and the identification of growth-related genes in bivalves could contribute to a better understanding of the mechanism governing their growth, which may benefit high-yielding bivalve breeding. Somatostatin receptor (SSTR) is a conserved negative regulator of growth in vertebrates. Although SSTR genes have been identified in invertebrates, their involvement in growth regulation remains unclear. Here, we identified seven SSTRs (PySSTRs) in the Yesso scallop, Patinopecten yessoensis, which is an economically important bivalve cultured in East Asia. Among the three PySSTRs (PySSTR-1, -2, and -3) expressed in adult tissues, PySSTR-1 showed significantly lower expression in fast-growing scallops than in slow-growing scallops. Then, the function of this gene in growth regulation was evaluated in dwarf surf clams (Mulinia lateralis), a potential model bivalve cultured in the lab, via RNA interference (RNAi) through feeding the clams Escherichia coli containing plasmids expressing double-stranded RNAs (dsRNAs) targeting MlSSTR-1. Suppressing the expression of MlSSTR-1, the homolog of PySSTR-1 in M. lateralis, resulted in a significant increase in shell length, shell width, shell height, soft tissue weight, and muscle weight by 20%, 22%, 20%, 79%, and 92%, respectively. A transcriptome analysis indicated that the up-regulated genes after MlSSTR-1 expression inhibition were significantly enriched in the fat digestion and absorption pathway and the insulin pathway. In summary, we systemically identified the SSTR genes in P. yessoensis and revealed the growth-inhibitory role of SSTR-1 in bivalves. This study indicates the conserved function of somatostatin signaling in growth regulation, and ingesting dsRNA-expressing bacteria is a useful way to verify gene function in bivalves. SSTR-1 is a candidate target for gene editing in bivalves to promote growth and could be used in the breeding of fast-growing bivalves.
Asunto(s)
Bivalvos , Pectinidae , Receptores de Somatostatina , Animales , Pectinidae/genética , Pectinidae/crecimiento & desarrollo , Pectinidae/metabolismo , Bivalvos/genética , Bivalvos/crecimiento & desarrollo , Bivalvos/metabolismo , Receptores de Somatostatina/genética , Receptores de Somatostatina/metabolismo , Filogenia , Interferencia de ARN , Regulación del Desarrollo de la Expresión GénicaRESUMEN
Scallops are rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid but perishable due to their microbial growth and lipid oxidation. In this study, gelatin/dextran films containing cinnamaldehyde and α-tocopherol (0% + 0%, 0.3% + 0.3%, 0.6% + 0.6%, 0.9% + 0.9%, and 1.2% + 1.2%, w/w) as active fillers were developed by solution casting method, and their preservation effects on scallop adductor muscle refrigerated at 4°C for 0, 3, 6, 9, and 12 days were evaluated. Inclusion of the two active fillers did not influence the thermal stability of the films but created heterogenous and discontinuous film microstructure and increased the film hydrophobicity. Increase in the concentrations of active fillers lowered the mechanical properties and water vapor permeability of the films but increased their crystallinity, thickness, water contact angle, opacity, antibacterial property, and antioxidant property. The longest release times for both cinnamaldehyde and α-tocopherol were found in 95% (v/v) ethanol solution. The gelatin/dextran films containing 1.2% (w/w) of active fillers (Gelatin [Ge]/Dextran [Dx]/1.2 film) improved the chemical stability of refrigerated scallop adductor muscle. The total viable count (TVC) of the unpackaged scallop adductor muscle exceeded the recommended limit of 7 lg CFU/g on day 6 (7.07 ± 0.50 lg CFU/g), whereas the TVC of the Ge/Dx/1.2 film-packaged scallop adductor muscle was still below the limit on day 9 (5.60 ± 0.50 lg CFU/g). Thus, the Ge/Dx/1.2 film can extend the shelf life of refrigerated scallop adductor muscle by at least 3 days. Overall, the developed gelatin/dextran active packaging films are promising for the preservation of aquatic food products.