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1.
Fish Shellfish Immunol ; 152: 109786, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39047925

RESUMEN

M. japonicus is an important specie for factory farming, and factory farming requires an environment with sand at the bottom of the pond. However, the physiological responses as well as survival in the process of factory farming without laying sand are currently unknown. In the present study, we explored the effect of sand substrate removal on the intestinal histomorphology, antioxidant enzyme activity, and metabolic profile of M. japonicus. Our results indicate a gradual increase in the mortality rate of kuruma shrimp in ponds lacking sand substrate. The intestinal mucosa exhibited necrosis and the presence of vacuoles, with their number gradually increasing over time. The intestinal villi showed significant erosion, accompanied by a decrease in intestinal superoxide dismutase (SOD) activity and catalase (CAT) activity, and consistent with an upregulation in the expression of apoptosis-related genes such as caspase-3, indicating an adaptive response to the adverse environmental conditions. Additionally, the metabolomic analysis revealed that most significantly differential metabolites were linked to amino acid and lipid metabolism. These findings enhance our understanding of the sand substrate removal on the intestinal health of kuruma shrimp, which provides a basis for the factory farming.


Asunto(s)
Antioxidantes , Intestinos , Penaeidae , Animales , Penaeidae/metabolismo , Penaeidae/inmunología , Penaeidae/genética , Antioxidantes/metabolismo , Arena , Acuicultura
2.
Ecotoxicol Environ Saf ; 282: 116690, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38981394

RESUMEN

Heterosigma akashiwo is a harmful algal bloom species that causes significant detrimental effects on marine ecosystems worldwide. The algicidal bacterium Pseudalteromonas sp. LD-B1 has demonstrated potential effectiveness in mitigating these blooms. However, the molecular mechanisms underlying LD-B1's inhibitory effects on H. akashiwo remain poorly understood. In this study, we employed the comprehensive methodology, including morphological observation, assessment of photosynthetic efficiency (Fv/Fm), and transcriptomic analysis, to investigate the response of H. akashiwo to LD-B1. Exposure to LD-B1 resulted in a rapid decline of H. akashiwo's Fv/Fm ratio, with cells transitioning to a rounded shape within 2 hours, subsequently undergoing structural collapse and cytoplasmic leakage. Transcriptomic data revealed sustained downregulation of photosynthetic genes, indicating impaired functionality of the photosynthetic system. Additionally, genes related to the respiratory electron transfer chain and antioxidant defenses were consistently downregulated, suggesting prolonged oxidative stress beyond the cellular antioxidative capacity. Notably, upregulation of autophagy-related genes was observed, indicating autophagic responses in the algal cells. This study elucidates the molecular basis of LD-B1's algicidal effects on H. akashiwo, advancing our understanding of algicidal mechanisms and contributing to the development of effective strategies for controlling harmful algal blooms.


Asunto(s)
Floraciones de Algas Nocivas , Fotosíntesis , Fotosíntesis/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Dinoflagelados/fisiología , Estramenopilos , Autofagia/efectos de los fármacos
3.
Appl Opt ; 61(4): 995-1000, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35201074

RESUMEN

The output performance of the spaceborne fiber amplifier will degrade when exposed to radiation in aerospace environment. In this work, we have proposed a two-stage erbium-ytterbium-co-doped fiber amplifier (EYDFA) and studied the degradation performance under irradiation and recovery through the annealing process without employing any additional device. An irradiation experiment is conducted to test the performances of the amplifier under the irradiation environment, and experimental results indicate that the output power as well as optical signal-to-noise ratio (OSNR) exhibit similar irradiation responses. The amplifier was annealed through photobleaching and natural annealing processes. The output performance almost recovers to its initial level, and it is verified that the annealing efficiency for high intensity photobleaching is about 240 times as much as that for the case of natural annealing. This work confirms that the spaceborne fiber amplifier could achieve performance recovery after being irradiated, which is beneficial to the enhancement of the radiation hardness for future spaceborne fiber optical devices.

4.
J Cell Mol Med ; 25(22): 10627-10637, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34697900

RESUMEN

Prostate cancer is the second most frequent malignancy in men worldwide, and its incidence is increasing. Therefore, it is urgently required to clarify the underlying mechanisms of prostate cancer. Although the long non-coding RNA LINC00115 was identified as an oncogene in several cancers, the expression and function of LINC00115 in prostate cancer have not been explored. Our results showed that LINC00115 was significantly up-regulated in prostate cancer tissues, which was significantly associated with a poor prognosis for prostate cancer patients. Functional studies showed that knockdown LINC00115 inhibited cell proliferation and invasion. In addition, LINC00115 served as a competing endogenous RNA (ceRNA) through sponging miR-212-5p to release Frizzled Family Receptor 5 (FZD5) expression. The expression of miR-212-5p was noticeably low in tumour tissues, and FZD5 expression level was down-regulated with the knockdown of LINC00115. Knockdown LINC00115 inhibited the Wnt/ß-catenin signalling pathway by inhibiting the expression of FZD5. Rescue experiments further showed that LINC00115 inhibits prostate cancer cell proliferation and invasion via targeting miR-212-5p/ FZD5/ Wnt/ß-catenin axis. The present study provided clues that LINC00115 may be a promising novel therapeutic target for prostate cancer patients.


Asunto(s)
Receptores Frizzled/genética , MicroARNs/genética , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , ARN Largo no Codificante/genética , Vía de Señalización Wnt , Adulto , Biomarcadores de Tumor , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Interferencia de ARN , Adulto Joven
5.
Ecotoxicol Environ Saf ; 207: 111485, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33254386

RESUMEN

Polychlorinated biphenyls (PCBs) are well-known persistent organic pollutants; they have toxic effects on the immune system, reproductive system, and endocrine system by changing the metabolism of the body. To elucidate the underlying molecular mechanism, the clam Meretrix meretrix was exposed to 10 and 1000 ng/L Aroclor 1254 and natural seawater (control). Samples from clams exposed to natural seawater and those exposed to Aroclor 1254 for 1 and 3 days were individually collected for transcriptome analysis. After assembly, more than 535,157 transcripts with a mean length of 949 bp and an N50 length of 1279 bp were obtained; a final set of 177,142 unigenes was generated. In the present study, 5101 differentially expressed genes were identified. The differentially expressed genes were related to detoxification metabolism, oxidative stress, immune response, and endocrine system disruption. Of these genes, under the Aroclor 1254 exposure, cytochrome P450 20A1 (2.06-4.46 folds), glutathione S-transferase (2.25-3.80 folds), multidrug resistance-associated protein 1-like (1.49-2.92 folds), peroxidase-like protein (1.33-4.26 folds), lysozyme (1.61-2.05 folds), bcl-2 like 1 protein (1.14-2.29 folds) and vitellogenin (1.09-1.19 folds) showed been significantly induced expressed. At the same time, some genes were down regulated, including cytochrome P450 2J5 (-1.20 ~ -2.86 folds), cytochrome P450 3A24 (-1.40 ~ -4.08 folds), C1q (-1.27 ~ -1.66 folds), Sulfotransferase (-1.51 ~ -1.84 folds), monocarboxylate transporter 10 (-1.30 ~ -4.70 folds), 3-beta hydroxysteroid dehydrogenase (-1.43 ~ -2.81 folds) and beta-galactosidase (-1.23 ~ -2.23 folds). Furthermore, it showed that the expression levels of CYP2J5, glutathione S-transferase, 3-beta hydroxysteroid dehydrogenase and beta-galactosidase had time responses and dose responses. The present study provided insights into the toxic effects of Aroclor 1254 exposure in M. meretrix.


Asunto(s)
Bivalvos/fisiología , Transcriptoma/fisiología , Contaminantes Químicos del Agua/toxicidad , Animales , Bivalvos/efectos de los fármacos , Citocromo P-450 CYP2J2 , Sistema Enzimático del Citocromo P-450/metabolismo , Glutatión Transferasa/metabolismo , Oxidación-Reducción , Estrés Oxidativo , Bifenilos Policlorados
6.
J Xray Sci Technol ; 29(3): 541-549, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33749630

RESUMEN

INTRODUCTION: It is a challenge to make accurate pre-surgical diagnosis for renal tumors. This study is to report the findings, management, and outcome of one rare case of ossification in a cystic renal mass. We present and discuss the pathological characteristics, radiologic features, and treatment alternatives of the patient. PATIENTS AND METHODS: A 38 years old female patient had intermittent epigastric pain and microscopic hematuria for two months. Computerized tomography (CT) scan and Magnetic Resonance imaging (MRI) showed a mass with rough edge and dense calcification in the upper pole of the right kidney and normal left kidney. Pre-operative diagnosis is cystic nephroma or cystic renal mass (Bosniak III type, Bosniak renal cyst classification). GFR was within normal limits for age and no other significant laboratory aberrations were noted. Patient underwent a right retroperitoneal laparoscopic partial nephrectomy (margin status was negative). A mini literature review was performed to highlight the principals of diagnosis and treatment of cystic renal mass with heterotopic ossification. RESULTS: The entire renal mass was successfully removed from upper pole of the right kidney by laparoscopic nephron sparing surgery. The size of renal mass is 38×35×30 mm3 with thick and hard capsular wall. The cystic cavity contains yellow lipid-like substances without stone. Histological examination revealed renal cyst in which the cyst wall reveals fibrosis and no obvious lining epithelium. The additional unique feature includes the presence of dense calcification and ossification in the renal mass. Localization tissue of yellow bone marrow was detected. No complications occurred in 9 months after surgery during follow-up. CONCLUSIONS: Cystic renal mass with heterotopic ossification is a rare case of non-malignant renal tumor. Whether surgery is needed depends to whether patients have symptoms. For symptom renal tumors, laparoscopic nephron sparing surgical procedure is recommended. Furthermore, complete surgical resection of the lesion is needed when the mass is suspected to be malignant. An accurate histologic diagnosis is key in its diagnosis.


Asunto(s)
Calcinosis , Enfermedades Renales Quísticas , Neoplasias Renales , Osificación Heterotópica , Adulto , Femenino , Humanos , Riñón/diagnóstico por imagen , Enfermedades Renales Quísticas/diagnóstico por imagen , Enfermedades Renales Quísticas/cirugía , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/cirugía , Osificación Heterotópica/diagnóstico por imagen , Osificación Heterotópica/cirugía
7.
Ecotoxicol Environ Saf ; 133: 381-9, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27497785

RESUMEN

The aryl hydrocarbon receptor (AhR) belongs to the basic-helix-loop helix (bHLH) Per-Arnt-Sim (PAS) family of transcription factors. AhR has been known primarily for its role in the regulation of several drug and xenobiotic metabolizing enzymes, as well as the mediation of the toxicity of certain xenobiotics, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Although the AhR is well-studied as a mediator of the toxicity of certain xenobiotics in marine bivalves, the normal physiological function remains unknown. In order to explore the function of the AhR, the bait protein expression plasmid pGBKT7-CfAhR and the cDNA library of gill from Chlamys farreri were constructed. By yeast two hybrid system, after multiple screening with the high screening rate medium, rotary verification, sequencing and bioinformatics analysis, the interactions of the CfAhR with receptor for activated protein kinase C 1 (RACK1), thyroid peroxidase-like protein (TPO), Toll-like receptor 4(TLR 4), androglobin-like, store-operated Ca(2+) entry (SocE), ADP/ATP carrier protein, cytochrome b, thioesterase, actin, ferritin subunit 1, poly-ubiquitin, short-chain collagen C4-like and one hypothetical protein in gill cells were identified. This study suggests that the CfAhR played fundamental roles in immune system homeostasis, oxidative stress response, and in grow and development of C. farreri. The elucidation of these protein interactions is of much importance both in understanding the normal physiological function of AhR, and as potential targets for further research on protein function in AhR interactions.


Asunto(s)
Pectinidae/metabolismo , Proteínas/metabolismo , Receptores de Hidrocarburo de Aril/metabolismo , Animales , ADN Complementario , Branquias/metabolismo , Receptores de Hidrocarburo de Aril/genética , Saccharomyces cerevisiae/metabolismo , Xenobióticos/metabolismo
8.
Ecotoxicol Environ Saf ; 115: 126-36, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25686690

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are known for their carcinogenic, teratogenic and mutagenic properties. Benzo(a)pyrene (BaP) possesses the greatest carcinogenic potential among the various PAHs. In this study, digital gene expression (DGE) was performed to investigate the digestive gland transcriptome profile of the clam Ruditapes philippinarum exposed to BaP. A total of 10,508,312 and 11,414,297 clean reads were generated respectively, from control and BaP exposure DGE libraries. One hundred and forty-five differentially expressed genes were detected after comparing two libraries with 58 up-regulated and 87 down-regulated genes. GO annotation and KEGG pathway analyses were performed on all genes to understand their biological functions and processes. The results showed that numerous enriched differentially expressed genes are related to growth and development, antioxidant metabolism, apoptosis and detoxification metabolism. Quantitative real-time PCR was performed to verify the expressed genes of DGE. Our results provide evidences that RNA-seq is a powerful tool for toxicology and capable of generating novel and valuable information at the transcriptome level for characterizing deleterious effects caused by BaP.


Asunto(s)
Benzo(a)pireno/toxicidad , Bivalvos/efectos de los fármacos , Carcinógenos/toxicidad , Transcriptoma/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Bivalvos/genética , Bivalvos/metabolismo , Perfilación de la Expresión Génica , Hidrocarburos Policíclicos Aromáticos/toxicidad , Análisis de Secuencia de ARN
9.
Ecotoxicol Environ Saf ; 110: 136-42, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25238485

RESUMEN

ATP-binding cassette transmembrane transporters (ABC transporters) have a potential role in xenobiotic resistance. In this study, we cloned full-length cDNA encoding an important ABC transporter, P-glycoprotein (Pgp) homologue from scallop Chlamys farreri (designated Cf-Pgp). The Cf-Pgp sequence is constituted by an ORF of 4152bp encoding for 1383 amino acids (GenBank accession no. ACL80139). The predicted molecular weight is 150.7kDa. The comparison of the deduced amino acid sequences with the Pgps from vertebrates showed high conservation of the residues and domains essential to the function of Pgp, including the ATP-binding cassettes and transmembrane domains. The mRNA expression of Cf-Pgp was detected in gill, digestive gland, mantle, hemocyte, adductor muscle and mature male and female gonad. We then utilized the real-time PCR to study expression levels of the Cf-Pgp gene in response to exposure of benzo(a)pyrene (BaP), tetrabromobisphenol A (TBBPA) and endosulfan (ES) (0.05, 0.5µg/L and 5µg/L) for 96 hours. The results showed that Cf-Pgp was significantly upregulated in the gill upon exposure to TBBPA and ES, but downregulated in the gill after exposure to BaP. These results suggested that the Cf-Pgp was a constitutive and inducible acute-phase protein that perhaps involved in the xenobiotic resistance of scallop C. farreri.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Benzo(a)pireno/toxicidad , Endosulfano/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , Pectinidae/efectos de los fármacos , Pectinidae/genética , Bifenilos Polibrominados/toxicidad , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Secuencia de Aminoácidos , Animales , Clonación Molecular , ADN Complementario/genética , ADN Complementario/metabolismo , Datos de Secuencia Molecular , Especificidad de Órganos , Pectinidae/metabolismo , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Alineación de Secuencia , Contaminantes Químicos del Agua/toxicidad
10.
Ecotoxicol Environ Saf ; 110: 190-6, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25244687

RESUMEN

Benzo[a]pyrene (BaP) is a representative polycyclic aromatic hydrocarbon (PAH) and is studied widely for its strong toxicity and wide distribution. Although BaP pollution in marine environment is increasing, molecular mechanisms underlying reproductive toxicity of BaP in marine mollusks have been seldom systematically studied, especially in males. In this study, genes that regulated reproductive responses of Chlamys farreri under BaP stress were analyzed through digital gene expression (DGE) sequencing with testis tissues. A total of 12,485,055 and 14,454,127 clean reads were generated from control and BaP exposure DGE libraries, respectively. After comparing two libraries, 1051 differentially expressed genes were detected, with 223 up-regulated and 828 down-regulated genes. Gene ontology (GO) annotation and kyoto encyclopedia of genes and genomes (KEGG) pathway analyses were performed on all genes to understand their biological functions and processes. The results showed that numerous enriched, differentially expressed genes related to aromatic compound catabolic processes, spermatid development, microtubule-based movement, energy production and immune response. Quantitative real-time PCR was performed to verify the expressed genes of DGE. The study generated data to show the overall reproductive transcription responses of male C. farreri under BaP stress, and it also can serve as the reference for future study of organic pollutions in aquatic mollusks.


Asunto(s)
Benzo(a)pireno/toxicidad , Pectinidae/efectos de los fármacos , Animales , Mapeo Cromosómico , Biología Computacional , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Biblioteca de Genes , Masculino , Pectinidae/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducción/efectos de los fármacos , Reproducción/genética
11.
Ecotoxicol Environ Saf ; 107: 251-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25011122

RESUMEN

A study was performed on clams (Ruditapes philippinarum) exposed to 0.03, 0.3 and 3µg/L benzo[a]pyrene (B[a]P) for 21 days. B[a]P metabolite contents, activities of aryl hydrocarbon hydroxylase (AHH), 7-ethoxyresorufin O-deethylase (EROD), epoxide hydrolase (EH), dihydrodiol dehydrogenase (DD), glutathione-S-transferase (GST), sulfotransferase (SULT) and uridinediphosphate glucuronyltransferase (UGT) and B[a]P bioaccumulation were assayed in gills and digestive glands. Results showed that the order of B[a]P phase I metabolite contents was 9-hydroxy-B[a]P>B[a]P-1,6-dione>B[a]P-7,8-dihydrodiol, and the concentration of B[a]P-7,8-dihydrodiol sulfate conjugates was higher than that of B[a]P-7,8-dihydrodiol glucuronide conjugates. B[a]P accumulation and the activities of AHH, EROD, EH, DD, SULT and UGT increased first and then reached equilibrium. GST activity was induced first and then depressed. The concentration of B[a]P was far higher than that of its metabolites. Besides, there were no significant differences between enzyme activities in gills and those in digestive glands. These results provided information on B[a]P metabolic mechanism in bivalve and scientific data for pollution monitoring and food security.


Asunto(s)
Benzo(a)pireno/metabolismo , Bivalvos/enzimología , Contaminantes Químicos del Agua/metabolismo , Animales , Benzo(a)pireno/análisis , Benzo(a)pireno/toxicidad , Bivalvos/química , Bivalvos/efectos de los fármacos , Citocromo P-450 CYP1A1/metabolismo , Monitoreo del Ambiente , Femenino , Branquias/química , Branquias/enzimología , Glutatión Transferasa/metabolismo , Masculino , Mariscos/análisis , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
12.
Artículo en Inglés | MEDLINE | ID: mdl-38857132

RESUMEN

Transformer-based one-stream trackers are widely used to extract features and interact information for visual object tracking. However, the current one-stream tracker has fixed computational dimensions between different stages, which limits the network's ability to learn context clues and global representations, resulting in a decrease in the ability to distinguish between targets and backgrounds. To address this issue, a new scalable one-stream tracking framework, ScalableTrack, is proposed. It unifies feature extraction and information integration by intrastage mutual guidance, leveraging the scalability of target-oriented features to enhance object sensitivity and obtain discriminative global representations. In addition, we bridge interstage contextual cues by introducing an alternating learning strategy and solve the arrangement problem of the two modules. The alternating learning strategy uses alternate stacks of feature extraction and information interaction to focus on tracked objects and prevent catastrophic forgetting of target information between different stages. Experiments on eight challenging benchmarks (TrackingNet, GOT-10k, VOT2020, UAV123, LaSOT, LaSOT [Formula: see text] , OTB100, and TC128) show that ScalableTrack outperforms state-of-the-art (SOTA) methods with better generalization and global representation ability.

13.
Biology (Basel) ; 13(3)2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38534444

RESUMEN

The receptor for activated protein kinase C1 (RACK1) belongs to the typical WD repeat family, which is extremely conservative and important in multiple signal transduction pathways related to growth and development that coordinate the intracellular role of various life activities. As a novel protein with versatile functions, it was found in a variety of organisms. In a previous study, we identified the RACK1 sequence of white shrimp from transcriptome data. In this study, we employed specialized bioinformatics software to conduct an in-depth analysis of EcRACK1 and compare its amino acid sequence homology with other crustaceans. Furthermore, we investigated the expression patterns of RACK1 at different developmental stages and tissues, as well as at various time points after exposure to Aroclor 1245, aiming to elucidate its function and potential response towards Aroclor 1245 exposure. The length of EcRACK1 is 957 nucleotides, which encodes 318 amino acids. Moreover, there were seven typical WD repeats in EcRACK1, which have more than a 96% sequence identity with the RACK1 proteins of Penaeus. The results of tissue expression and spatiotemporal expression showed that it was significantly increased in the II and IV stages, but had a significant tissue specificity in the hepatopancreas, spermary, and muscle tissues of E. carinicauda, adult stage. Compared to the control, EcRACK1 was significantly induced in E. carinicauda zoea larvae exposed to Aroclor 1254 for 6, 10, 20, and 30 d (p < 0.05). These results suggested that EcRACK1 may play an important role in the larval development and environmental defense of E. carinicauda.

14.
Mitochondrial DNA B Resour ; 9(1): 29-32, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38187008

RESUMEN

Barnacles are crustaceans that are critical model organisms in intertidal ecology and biofouling research. In this study, we present the first mitochondrial genome of Striatobalanus tenuis which is a circular molecule of 15,067 bp in length. Consistent with most barnacles, the mitochondrial genome of S. tenuis encodes 37 genes, including 13 PCGs, 22 tRNAs and 2 rRNAs. A novel insight into the phylogenetic analysis based on the nucleotide data of 13 PCGs showed that the S. tenuis clusters with Striatobalanus amaryllis (bootstrap value = 100) of the same genus, then groups with other Balanoidea species, the Chelonibiidae, Austrobalanidae and Tetraclitidae cluster together forming superfamily Coronuloidea. The result can help us to understand the novel classification within Balanomorpha.

15.
Sci Total Environ ; 945: 173913, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38880157

RESUMEN

The globally distributed harmful algal blooms (HAB) species, Heterosigma akashiwo, has been found to exhibit ichthyotoxicity. Previous studies have shown that H. akashiwo achieves a competitive edge during bloom occurrences by inhibiting the growth of a coexisting diatom, Skeletonema costatum, through allelopathy. However, the specific allelopathic mechanisms underlying the allelopathic effects of H. akashiwo on S. costatum remain unknown. To bridge this gap, our study utilized a combination of quantitative real-time PCR and metabolomics to examine the allelopathic processes of H. akashiwo on S. costatum. Our results demonstrate that the growth of S. costatum is hindered when co-cultured with H. akashiwo (initial cell concentration, 2 × 104 cell/mL). Gene expression investigation showed a substantial reduction in the mRNA levels of cytochrome b6, ribulose bisphosphate carboxylase large chain, and silicon transporter in S. costatum when grown in co-culture conditions. Furthermore, metabolic pathway analysis suggested that the allelopathic effects of H. akashiwo disrupted several vital metabolic pathways in S. costatum, including a reduction in purine and pyrimidine metabolism and an increase in fatty acid biosynthesis. Our investigation has revealed the intricate and substantial involvement of allelopathy in the formation of H. akashiwo blooms, demonstrating the complexity of the allelopathic interaction between H. akashiwo and S. costatum. These insights also contribute significantly to our understanding of the dynamics within HAB species.


Asunto(s)
Alelopatía , Diatomeas , Floraciones de Algas Nocivas , Metabolómica , Diatomeas/fisiología , Expresión Génica , Dinoflagelados/fisiología , Dinoflagelados/genética , Estramenopilos/fisiología
16.
Harmful Algae ; 133: 102601, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38485440

RESUMEN

The photoperiod, which is defined as the period of time within a 24-hour time frame that light is available, is an important environmental regulator of several physiological processes in phytoplankton, including harmful bloom-forming phytoplankton. The ichthyotoxic raphidophyte Heterosigma akashiwo is a globally distributed bloom-forming phytoplankton. Despite extensive studies on the ecological impact of H. akashiwo, the influence of the photoperiod on crucial biological processes of this species remains unclear. In this study, gene expression in H. akashiwo was analyzed over a 24-hour light-dark (14:10) treatment period. Approximately 36 % of unigenes in H. akashiwo were differentially expressed during this 24-hour treatment period, which is indicative of their involvement in the response to light-dark variation. Notably, the number of differentially expressed genes exhibited an initial increase followed by a subsequent decrease as the sampling time progressed (T0 vs. other time points). Unigenes associated with photosynthesis and photoprotection reached their peak expression levels after 2-4 h of illumination (T12-T14). In contrast, the expression of unigenes associated with DNA replication peaked at the starting point of the dark period (T0). Furthermore, although several unigenes annotated to photoreceptors displayed potential diel periodicity, genes from various photoreceptor families (such as phytochrome and cryptochrome) showed unique expression patterns. Collectively, our findings offer novel perspectives on the response of H. akashiwo to the light-dark cycle, serving as a valuable resource for investigating the physiology and ecology of this species.


Asunto(s)
Dinoflagelados , Estramenopilos , Fotoperiodo , Dinoflagelados/genética , Fitoplancton/genética , Perfilación de la Expresión Génica , Fotosíntesis , Estramenopilos/genética
17.
Microorganisms ; 11(2)2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36838354

RESUMEN

The raphidophyte Heterosigma akashiwo is a harmful algal species. The bloom of this organism has been associated with the massive mortality of fish in many coastal waters. To investigate the molecular mechanism of H. akashiwo blooms, having a reliable reference transcriptome of this species is essential. Therefore, in this study, a full-length transcriptome of H. akashiwo was obtained by single-molecule real-time sequencing. In total, 45.44 Gb subread bases were generated, and 16,668 unigenes were obtained after the sequencing data processing. A total of 8666 (52.00%) unigenes were successfully annotated using seven public databases. Among them, mostly phosphorus and nitrogen metabolism genes were detected. Moreover, there were 300 putative transcription factors, 4392 putative long non-coding RNAs, and 7851 simple sequence repeats predicted. This study provides a valuable reference transcriptome for understanding how H. akashiwo blooms at a molecular level.

18.
Environ Technol ; 44(17): 2607-2616, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35099361

RESUMEN

Harmful algae blooms (HABs) have increased in intensity and frequency worldwide, causing negative effects on public health and marine ecosystems. This study isolated and identified the bloom causing species and its associated algicidal bacterium during a phytoplankton bloom in coastal waters of Lianyungang, China. Morphological observations and DNA barcoding analysis indicate that the studied phytoplankton bloom was caused by the raphidophyte Heterosigma akashiwo, and the algicidal bacterium, strain LD-B1, was identified as a species belonging to the genus Pseudoalteromonas. Furthermore, the algicidal effects of strain LD-B1 against H. akashiwo were characterized; revealing strain LD-B1 show strong algicidal activity against H. akashiwo. After 48 h of bacterium culture addition, the algicidal rate reached up to 98.8% with a 1% final volume rate. Moreover, our findings indicate strain LD-B1's extracellular compounds involved in algicidal activity are likely not proteinaceous. These findings indicate that the isolated strain, LD-B1, is a promising algicidal bacterium to control H. akashiwo blooms.


Asunto(s)
Dinoflagelados , Ecosistema , Bacterias , Floraciones de Algas Nocivas , Fitoplancton , China
19.
Front Microbiol ; 13: 1091561, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36619989

RESUMEN

The dinoflagellate Noctiluca scintillans is a harmful algal species that is globally distributed and poses a certain threat to marine ecosystems. Recent research has shown that the application of algicidal bacteria is a promising method to prevent and control such harmful algal blooms (HABs), given its advantages of safety and efficiency. In this study, a strain of algicidal bacterium LD-B6 with high efficiency against N. scintillans was isolated from the coastal waters of Lianyungang, China. 16S rDNA sequence analysis showed that the strain LD-B6 belongs to the genus Pseudoalteromonas. Furthermore, the algicidal effect of LD-B6 on N. scintillans was investigated. The results showed that strain LD-B6 exerted strong algicidal activity against N. scintillans. After 12 h of bacterial culture addition to algal cultures at a 2% final volume rate, the algicidal activity reached 90.5%, and the algicidal activity of LD-B6 was influenced by the density of N. scintillans. In addition, the algicidal bacterium LD-B6 was found to indirectly lyse algal cells by secreting extracellular compounds. These algicidal compounds were stable, indicating that they are not proteins. Importantly, strain LD-B6 was broadly general, showing varying degrees of lysing effects against five of the six algal species tested. On the basis of the described studies above, the algicidal powder was also initially developed. In summary, the isolated bacterial strain LD-B6 shows the potent algicidal capability to serve as a candidate algicidal bacterium against N. scintillans blooms.

20.
Mitochondrial DNA B Resour ; 6(6): 1740-1742, 2021 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-34104756

RESUMEN

The triangle barnacle Balanus trigonus Darwin, 1854, a cosmopolitan inhabitant of tropical and warm temperate seas, is a member of robust system for the study of evolutionary processes in the intertidal zone. The first mitochondrial genome of B. trigonus is presented. The complete mitochondrial genome of B. trigonus is a circular molecule of 15,560 bp, which encodes 13 protein-coding genes (PCGs), 2 rRNA genes, and 22 tRNA genes. In comparison within Sessilia, the arrangement of the mitochondrial genome of B. trigonus is more similar to Megabalanus spp. than the congener Balanus balanus, which share a same inversion of a large gene block (P-nd4L-nd4-H-nd5-F). Phylogenetic analysis based on mitochondrial PCGs reveals that B. trigonus clusters with Acasta Sulcata (BP = 100), then grouped with Megabalanus volcano and Megabalanus ajax with high support (BP = 90). In further, more data and research are needed to reveal the phylogeny within Cirripedia.

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