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1.
Hereditas ; 155: 36, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30473655

RESUMO

To develop a brackish water flea as a promising model for marine monitoring, Diaphanosoma celebensis were exposed to two pollutants, cadmium (Cd) and benzo[a]pyrene (BaP), which have different chemical characteristics and distinct modes of metabolic action on aquatic animals. Twenty-four hours after exposure to Cd (2 mg/L) or BaP (25 µg/L), whole body transcriptomes were analyzed. In total, 99.6 Mbp were assembled from nine libraries, resulting in 98,458 transcripts with an N50 of 1883 bp and an average contig length of 968 bp. Functional gene annotations were performed using Gene Ontology, Eukaryotic Orthologous Groups, and Kyoto Encyclopedia of Genes and Genomes pathway analyses. Cd significantly modulated endocrine and digestive enzyme system. Following BaP treatment, DNA repair and circadian rhythm related metabolisms were significantly modulated. Both the chemicals induced stress response and detoxification metabolism. This brackish water flea genomic information will be useful to monitor estuaries and coastal regions, as water fleas have been confirmed as promising sentinel models in freshwater ecosystems.


Assuntos
Benzo(a)pireno/toxicidade , Cádmio/toxicidade , Ritmo Circadiano/genética , Cladocera/genética , Reparo do DNA/genética , Transcriptoma , Poluentes Químicos da Água/toxicidade , Animais , Cladocera/efeitos dos fármacos , Ecotoxicologia , Perfilação da Expressão Gênica
2.
Aquat Toxicol ; 196: 35-42, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29328974

RESUMO

Because of its widespread use, the pharmaceutical acetaminophen (APAP) is frequently detected in aquatic environments. APAP can have serious physiological effects, such as reduced reproduction, low growth rates, and abnormal behavior, in aquatic organisms. However, the methods available for evaluation of the aquatic toxicity of APAP are of limited usefulness. The present study aimed to develop reliable and sensitive markers for evaluation of APAP toxicity using Daphnia as a model organism. We focused on N-acetyl-p-benzoquinoneimine (NAPQI) production from APAP via cytochrome P450 metabolism because NAPQI causes APAP toxicity. Daphnia magna were exposed to APAP (0, 50, or 100 mg/L for 12 h or 24 h), and the total metabolites were extracted and analyzed for NAPQI. Direct detection of NAPQI was difficult because of its high reactivity, and its peak was close to that for APAP. Therefore, we tried to identify molecular and biochemical indicators associated with NAPQI generation, elimination, and its interactions with macromolecules. We identified changes in CYP370A13 gene expression, glutathione depletion, inhibition of thioredoxin reductase activity, and production of reactive oxygen species as indicators of D. magna exposure to APAP. These indicators could be used to develop sensitive and accurate techniques to evaluate the environmental toxicity of APAP.


Assuntos
Acetaminofen/toxicidade , Sistema Enzimático do Citocromo P-450/metabolismo , Daphnia/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Acetaminofen/análise , Acetaminofen/metabolismo , Animais , Benzoquinonas/análise , Benzoquinonas/toxicidade , Cromatografia Líquida de Alta Pressão , Sistema Enzimático do Citocromo P-450/genética , Daphnia/metabolismo , Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Iminas/análise , Iminas/toxicidade , Inativação Metabólica , Masculino , Espécies Reativas de Oxigênio/metabolismo , Tiorredoxina Dissulfeto Redutase/metabolismo
3.
Bull Environ Contam Toxicol ; 98(2): 183-189, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27995293

RESUMO

Many studies of the toxic effects of zinc oxide nanoparticles (ZnO NPs) in aquatic organisms have been performed because of increasing ZnO NP use. However, the toxicological pathways are not understood. In this study, ZnO NPs were found to be more toxic than ZnSO4 to zebrafish larvae, but ZnO NP toxicity did not involve transcript alterations. Biological processes affected by ZnO NPs and ZnSO4 were investigated by performing ingenuity pathway analysis on differently expressed genes in larvae exposed to sub-lethal ZnO NP and ZnSO4 concentrations. We identified upregulated and downregulated differently expressed genes in fish exposed to ZnO NPs and ZnSO4, and found that ZnO NPs slightly induced cell differentiation and pathways associated with the immune system and activated several key genes involved in cancer cell signaling. The results may be key to predicting and elucidating the mechanisms involved in ZnO NP and ZnSO4 toxicity in zebrafish larvae.


Assuntos
Nanopartículas/toxicidade , Peixe-Zebra/genética , Óxido de Zinco/toxicidade , Sulfato de Zinco/toxicidade , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Exposição Ambiental , Regulação da Expressão Gênica/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/genética , Transdução de Sinais/efeitos dos fármacos
4.
Environ Toxicol Chem ; 35(6): 1449-57, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26496856

RESUMO

Chlorpyrifos is a widely used organophosphorus insecticide for controlling diverse insect pests of crops. In the monogonont rotifer Brachionus koreanus, population growth retardation with the inhibition of lifespan, fecundity, and individual body size of ovigerous females was shown over 10 d in response to chlorpyrifos exposure. At the molecular and biochemical levels, the rotifer B. koreanus defensome, composed of cytochrome P450 complements, heat shock protein 70, and antioxidant enzymatic systems (i.e., glutathione, glutathione peroxidase, glutathione reductase, and glutathione S-transferase), was significantly induced in response to different concentrations of chlorpyrifos. Thus, chlorpyrifos strongly induced a defensome system to mitigate the deleterious effects of chlorpyrifos at in vivo and in vitro levels as a trade-off in fitness costs. Environ Toxicol Chem 2016;35:1449-1457. © 2015 SETAC.


Assuntos
Antioxidantes/metabolismo , Clorpirifos/toxicidade , Sistema Enzimático do Citocromo P-450/metabolismo , Poluentes Ambientais/toxicidade , Estágios do Ciclo de Vida/efeitos dos fármacos , Rotíferos/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Clorpirifos/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Poluentes Ambientais/metabolismo , Feminino , Perfilação da Expressão Gênica , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Rotíferos/genética , Rotíferos/crescimento & desenvolvimento , Rotíferos/metabolismo
5.
Aquat Toxicol ; 140-141: 58-67, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23765029

RESUMO

To investigate effects of gamma ray irradiation in the hermaphroditic fish, Kryptolebias marmoratus larvae, we checked expression of p53, DNA repair, and heat shock protein genes with several antioxidant enzyme activities by quantitative real-time RT-PCR and biochemical methods in response to different doses of gamma radiation. As a result, the level of gamma radiation-induced DNA damage was initiated after 4Gy of radiation, and biochemical and molecular damage became substantial from 8Gy. In particular, several DNA repair mechanism-related genes were significantly modulated in the 6Gy gamma radiation-exposed fish larvae, suggesting that upregulation of such DNA repair genes was closely associated with cell survival after gamma irradiation. The mRNA expression of p53 and most hsps was also significantly upregulated at high doses of gamma radiation related to cellular damage. This finding indicates that gamma radiation can induce oxidative stress with associated antioxidant enzyme activities, and linked to modulation of the expression of DNA repair-related genes as one of the defense mechanisms against radiation damage. This study provides a better understanding of the molecular mode of action of defense mechanisms upon gamma radiation in fish larvae.


Assuntos
Ciprinodontiformes/fisiologia , Reparo do DNA , Raios gama , Regulação da Expressão Gênica/efeitos da radiação , Proteínas de Choque Térmico/genética , Oxirredutases/genética , Proteína Supressora de Tumor p53/genética , Animais , Reparo do DNA/genética , Reparo do DNA/efeitos da radiação , Ativação Enzimática/efeitos da radiação , Estresse Oxidativo/efeitos da radiação , Oxirredutases/metabolismo
6.
Comp Biochem Physiol C Toxicol Pharmacol ; 157(2): 172-82, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23178197

RESUMO

CYP1A is involved in the metabolism of diverse chemicals, including polycyclic aromatic hydrocarbons and alkylated-PAHs, as a first line of detoxification mechanism. First, we identified and characterized the CYP1A gene from the marine medaka, Oryzias melastigma. O. melastigma CYP1A (Om-CYP1A) showed a high similarity of motifs/domains compared to those of vertebrates in their amino acid sequences. To check whether the Om-CYP1A would be inducible, we tested two strong CYP1A inducers, ß-naphthoflavone (ß-NF) and benzo[α]pyrene (B[α]P), and observed concentration-dependent transient expression on transcripts of Om-CYP1A for 96 h over a wide range of concentrations. Om-CYP1A mRNA level was significantly increased in exposure to different concentrations of ß-NF and B[α]P, and its expression was highly transcribed within 12 h upon the exposure to low concentrations of both chemicals. Inducible transcript profiles revealed that Om-CYP1A would be associated with the toxicant metabolism via AhREs/DREs/XREs in its promoter region. To uncover the effects of the water-accommodated fraction (WAF) of crude oil on transcripts of Om-CYP1A, we measured mRNA expression of Om-CYP1A towards different concentrations of WAF for 24h. As a result, WAF exposure significantly increased Om-CYP1A transcripts at all concentrations as well as during time-course experiments for 96 h. In this paper, we demonstrated that WAF would trigger up-regulation of the CYP1A gene that would be associated with the initiation of the cellular defense systems. This finding provides a better understanding of the molecular mechanism of cellular protection particularly that involved in the WAF-mediated cellular response in O. melastigma.


Assuntos
Citocromo P-450 CYP1A1/genética , Proteínas de Peixes/genética , Oryzias/genética , Petróleo , Poluentes Químicos da Água/toxicidade , Sequência de Aminoácidos , Animais , Sequência de Bases , Benzo(a)pireno/metabolismo , Benzo(a)pireno/toxicidade , Biomarcadores/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Relação Dose-Resposta a Droga , Proteínas de Peixes/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Desintoxicação Metabólica Fase I , Dados de Sequência Molecular , Oryzias/crescimento & desenvolvimento , Oryzias/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Poluentes Químicos da Água/metabolismo , beta-Naftoflavona/metabolismo , beta-Naftoflavona/toxicidade
7.
Comp Biochem Physiol C Toxicol Pharmacol ; 155(2): 344-51, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22037546

RESUMO

To identify and evaluate potentially useful biomarkers for oxidative stress as early warning indices in the polychaete, Perinereis nuntia, we exposed P. nuntia to copper (Cu) and measured several biomarker enzymes (glutathione S-transferase; GST, glutathione peroxidase; GPx, Metallothionein-like protein; MTLPs, and catalase; CAT) and genes (Pn-GSTs, Pn-CAT, and Pn-MT) with a cellular oxidative index, reactive oxygen species (ROS) level. Accumulated Cu concentrations in P. nuntia increased in a time-dependent manner. Intracellular ROS reached high levels 6h after exposure in P. nuntia with an increase of GST activity and glutathione (GSH) content. Particularly, GSH in polychaetes showed a positive correlation with Cu contents accumulated in P. nuntia. Messenger RNA expressions of GST sigma and GST omega showed relatively high expressions at 50 µg/L of Cu exposure, even though the moderate increase of rest of GST isoforms was also observed. Also regarding long-term exposure, we reared P. nuntia in sediments for 15 days, and found that there was an obvious increase of Pn-GSTs, Pn-CAT, and Pn-MT genes with elevated concentrations of Cu and Cd in polychaete body, compared to initial levels, suggesting that P. nuntia in sediment was affected by metals as well as by other organic pollutants to induce oxidative stress genes and enzymes. These findings suggest that oxidative stress is a potential modulator of defense system of P. nuntia. Several potential biomarker genes are available as early warning signals for environmental biomonitoring.


Assuntos
Antioxidantes/metabolismo , Cobre/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Estresse Oxidativo , Poliquetos/metabolismo , Animais , Catalase/genética , Catalase/metabolismo , Cobre/metabolismo , Monitoramento Ambiental/métodos , Poluentes Ambientais/metabolismo , Poluentes Ambientais/toxicidade , Glutationa/metabolismo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Metalotioneína/genética , Metalotioneína/metabolismo , Poliquetos/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Artigo em Inglês | MEDLINE | ID: mdl-21612991

RESUMO

The self-fertilizing hermaphroditic fish, Kryptolebias marmoratus is considered a suitable model species in the fields of eco-biology, developmental biology, endocrinology, environmental genomics, aquatic toxicology, and molecular carcinogenesis. However, more extensive gene information is still needed to improve our understanding of the biology of this fish with respect to toxicological responses. We performed a transcriptomic study in this species using pyrosequencing. Liver and ovary mRNA was reverse synthesized into cDNA and randomly sequenced by a Roche 454, GS-20 sequencer. After quality assessment, the assembled expressed sequence tag (EST) translations were compared with the GenBank non-redundant (nr) amino acid sequence database using BLASTX. In the assembly stage 1, both 59,732 transcripts in liver and 103,526 transcripts in ovary were obtained. To identify the differently expressed genes in the ovary and liver tissues, all transcripts were sorted out with an expected value threshold of 1.00E-05. Consequently, 7168 contigs of ovary ESTs and 3855 contigs of liver ESTs were not overlapped for expression in both tissues, whereas 3763 contigs were commonly found in both tissues. Subsequently, we described the most highly represented genes in the liver and ovary of K. marmoratus. Isoforms of cytochrome P450 (CYP) and receptor-related genes showed tissue-preferential expressed patterns. To identify the potential biomarkers in this species, ovary and liver ESTs were assembled and annotated with the nr amino acid sequence database using BLASTX. Then, 35,471 transcripts were obtained, and 9130 transcripts were hit (26%) at the assembly stage 2. Finally, we identified a number of stress-, antioxidant defense-, and DNA repair-related genes as potential molecular biomarkers for toxicological response using this species. We discuss the potential use for these markers in K. marmoratus for environmental genomics and eco-toxicological studies to uncover mechanisms of environmental stresses and chemical toxicities to K. marmoratus.


Assuntos
Etiquetas de Sequências Expressas , Organismos Hermafroditas/genética , Peixes Listrados/anatomia & histologia , Peixes Listrados/genética , Fígado/fisiologia , Ovário/fisiologia , Animais , Biomarcadores , Bases de Dados Genéticas , Feminino , Humanos , Peixes Listrados/metabolismo , Poluentes Químicos da Água
9.
Artigo em Inglês | MEDLINE | ID: mdl-21458595

RESUMO

Glutathione S-transferase (GST) is a phase II enzyme that functions as a detoxicant by catalyzing the conjugation of reduced glutathione with a variety of xenobiotics via cysteine thiol. Molecular genetic approaches using gene biomarkers show substantial relevance as sensitive biomarkers for the indication of pollution levels. In order to use GSTs as molecular biomarkers for marine pollution monitoring, we cloned and sequenced the full-length cDNA of seven GST genes from the marine polychaete Perinereis nuntia. The deduced amino acid sequence of Pn-GSTs showed a high similarity to those of other species that clustered into the same clades in a phylogenetic analysis. In addition, to evaluate Pn-GSTs as useful biomarkers on effects after cadmium (Cd) exposure, we exposed sublethal concentrations of Cd (5, 50, and 500 µg/L) to P. nuntia, and they showed relatively different but significantly increases, depending on exposure time and Cd concentrations. Particularly, Pn-GST-omega and Pn-GST-sigma genes were highly sensitive with a clear dose-dependent manner on mRNA expression. The total GST activities also have significantly increased levels at higher concentrations of Cd exposure. These results indicate that Pn-GSTs play important roles in Cd-induced oxidative stress in terms of the physiological changes relating to metabolism and cell protection, and those genes would have great potential as molecular biomarkers to monitor marine environmental health.


Assuntos
Cloreto de Cádmio/toxicidade , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Poliquetos , Poluentes Químicos da Água/toxicidade , Sequência de Aminoácidos , Animais , Biomarcadores/metabolismo , Bases de Dados de Ácidos Nucleicos , Relação Dose-Resposta a Droga , Monitoramento Ambiental , Glutationa Transferase/classificação , Dados de Sequência Molecular , Filogenia , Poliquetos/classificação , Poliquetos/enzimologia , Poliquetos/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Especificidade da Espécie
10.
Artigo em Inglês | MEDLINE | ID: mdl-21377541

RESUMO

The monogonont rotifer, Brachionus sp. has been regarded as a potential model for reproductive physiology, evolution, and environmental genomics. To uncover the role of the heat shock protein upon temperature stress and hydrogen peroxide (H2O2) exposure, we cloned heat shock protein 20 (Hsp20) and determined its modulatory response under different temperatures and H2O2 concentrations. Under different temperature stresses (10 °C and 37 °C), the rotifer Brachionus sp. Hsp20 (Br-Hsp20) gene was highly expressed over time, and reached the maximum level 90 min after exposure, indicating that Br-Hsp20 gene would be involved in the chaperoning process to protect proteins at both low and high temperatures. To test the ability of thermotolerance of the recombinant Br-Hsp20-containing transformed Escherichia coli, we expressed the recombinant Br-Hsp20 protein with 1mM IPTG for 18 h at 30 °C, exposed them at 54 °C with time course (10 to 60 min), and measured cell survival. In this elevated temperature shock (54 °C), the cell survival was significantly higher at the Br-Hsp20 transformed E. coli, compared to the control (vector only). To analyze the modulatory effect of Br-Hsp20 gene on oxidative stress, we initially exposed 0.1 mM H2O2 over time and measured antioxidant enzyme activities along with the expression level of Br-Hsp20 mRNA. Upon H2O2 exposure, Br-Hsp20 gene was time-dependently upregulated and glutathione peroxidase (GPx), glutathione S-transferase (GST), and glutathione reductase (GR) activities were also elevated at the 12h-exposed group in a dose-dependent manner, indicating that the Br-Hsp20 gene would be an important gene in response to oxidative and temperature stress. Here, we demonstrated the role of the Hsp20 gene in the rotifer, Brachionus sp. providing a better understanding of the ecophysiology at environmental stress in this species.


Assuntos
Proteínas de Choque Térmico HSP20/genética , Proteínas de Helminto/genética , Peróxido de Hidrogênio/farmacologia , Rotíferos/genética , Temperatura , Sequência de Aminoácidos , Animais , Sequência de Bases , Escherichia coli/genética , Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Proteínas de Choque Térmico HSP20/classificação , Proteínas de Choque Térmico HSP20/metabolismo , Proteínas de Helminto/metabolismo , Viabilidade Microbiana/genética , Dados de Sequência Molecular , Oxidantes/farmacologia , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotíferos/metabolismo , Homologia de Sequência de Aminoácidos , Estresse Fisiológico , Transformação Genética
11.
Artigo em Inglês | MEDLINE | ID: mdl-20965277

RESUMO

O6-methylguanine-DNA methyltransferase (O6-MGMT; EC 2.1.1.63) is a key repair enzyme that helps to protect the cell against alkylation on DNA by removing a methyl group from the O6-position of guanine. Here, we cloned and sequenced the full-length O6-MGMT cDNA from the hermaphroditic fish, Kryptolebias marmoratus. Complete Km-O6-MGMT cDNA was 1324 bp in length, and the open reading frame of 567 bp encoded a polypeptide of 188 amino acid residues. Phylogenetic analysis revealed that Km-O6-MGMT was clustered with those of other fish species. Embryo, juveniles, and aged secondary fish had low levels of Km-O6-MGMT mRNA than adults, indicating more susceptibility to DNA damage by alkylating agent exposure during these developmental stages. Km-O6-MGMT mRNA levels differed according to tissue type and was highest in the liver. Exposure to an alkylating agent, N-methyl-N-nitrosourea (MNU) exposure increased the mRNA expression of tumor suppressor gene such as p53 and oncogenes such as R-ras1, R-ras3, N-ras, c-fos as well as Km-O6-MGMT mRNA in a time-dependent manner. On the contrary, several (anti)estrogenic compounds (17ß-estradiol 100 ng/L, tamoxifen 10 µg/L, bisphenol A 600 µg/L, and 4-tert-octylphenol 300 µg/L) suppressed mRNA expression of Km-O6-MGMT in most tissues, especially the liver. In juvenile fish, 17ß-estradiol, bisphenol A, and 4-tert-octylphenol also decreased the expression of Km-O6-MGMT mRNA in a time-dependent manner. Overall, our finding shows that Km-O6-MGMT mRNA levels can be modulated by environmental estrogenic compounds as well as alkylating agents. This finding will be helpful to improve our knowledge of the effects of estrogenic compounds that contain the genotoxic ability to inhibit the DNA repair process in aquatic animals.


Assuntos
Ciprinodontiformes/genética , Disruptores Endócrinos/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Organismos Hermafroditas/efeitos dos fármacos , O(6)-Metilguanina-DNA Metiltransferase/genética , Sequência de Aminoácidos , Animais , Ciprinodontiformes/metabolismo , Organismos Hermafroditas/genética , Organismos Hermafroditas/metabolismo , Dados de Sequência Molecular , O(6)-Metilguanina-DNA Metiltransferase/metabolismo , Filogenia , Análise de Sequência de DNA , Poluentes Químicos da Água/toxicidade
12.
Comp Biochem Physiol C Toxicol Pharmacol ; 152(4): 456-66, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20647052

RESUMO

Pituitary gonadotropins (GTHs), follicle stimulating hormone beta (FSH-beta), and luteinizing hormone beta (LH-beta) are the key hormones in the hypothalamus-pituitary-gonad (HPG) axis, and form the heterodimers between a common alpha subunit (gonadotropin-alpha) and FSH-beta and/or LH-beta. To obtain a better understanding on the modulation of gonadotropin subunit genes expression upon bisphenol A (BPA) exposure in hermaphroditic fish, we studied differential regulation of gonadotropin subunit genes from Kryptolebias marmoratus after the exposure of several EDCs. Expression profiles of these three genes when using quantitative real-time RT-PCR revealed that brain/pituitary tissues were highly expressed in these genes compared to other tissues. At different developmental stages, expression of those genes dramatically increased over the course of development but showed a decrease in expression at the secondary male (showing atresia) stage. When adult fish were exposed to BPA (600 microg/L for 96 h), a significant upregulation of these three genes was observed in the brain/pituitary. A time course study also revealed the increased expression of gonadotropin subunit genes over 12 h with a more pronounced effect on the expression of FSH-beta and LH-beta genes, indicating that both genes were associated with the BPA exposure on the transcriptional regulation. This is the first report of gonadotropin subunit genes from K. marmoratus, with particular emphasis on the modulation of their expressions by EDCs. In addition, these findings suggest that EDCs modulate the expression of gonadotropin subunit genes and would act as potential biomarkers upon EDCs exposure.


Assuntos
Ciprinodontiformes/genética , Estrogênios não Esteroides/toxicidade , Gonadotropinas Hipofisárias/genética , Organismos Hermafroditas/efeitos dos fármacos , Fenóis/toxicidade , Sequência de Aminoácidos , Animais , Compostos Benzidrílicos , Ciprinodontiformes/metabolismo , Relação Dose-Resposta a Droga , Estradiol/toxicidade , Subunidade beta do Hormônio Folículoestimulante/genética , Subunidade beta do Hormônio Folículoestimulante/metabolismo , Expressão Gênica/efeitos dos fármacos , Gonadotropinas Hipofisárias/metabolismo , Organismos Hermafroditas/genética , Organismos Hermafroditas/metabolismo , Hormônio Luteinizante Subunidade beta/genética , Hormônio Luteinizante Subunidade beta/metabolismo , Dados de Sequência Molecular , Filogenia , Tamoxifeno/toxicidade
13.
Artigo em Inglês | MEDLINE | ID: mdl-19393767

RESUMO

Choriogenins (Chgs) are precursors of inner layer of egg envelope that are synthesized in fish liver in response to estrogens. Therefore, study of their expression serves as biomarker of exposure to endocrine disrupting chemicals (EDCs). The self-fertilizing fish, Kryptolebias marmoratus has been established as a model species for testing the action of EDCs. To use this fish as a model for assessing estrogenic activity of EDCs on Chg expression, two K. marmoratus choreogenin genes, Km-ChgH and Km-ChgL were cloned and their expression was analyzed in different tissues and in developmental stages by real-time RT-PCR. Expression levels of liver mRNA were compared between hermaphrodites and secondary males after exposure to EDCs. Km-ChgH and Km-ChgL genes that were predominantly expressed in liver contained zona pellucida (ZP) domains. During embryonic development, low expression of mRNA was observed at stage 1 (2 dpf) that reached highest level at stage 4 (12 dpf) or stage 5 (5 h post hatching). The expression of Km-Chg mRNAs was highly increased in liver exposed to natural estrogen, 17alpha-estradiol (E2) as well as EDCs such as bisphenol A and 4-n-nonylphenol in both the gender types. Another EDC, 4-tert-octylphenol, showed modulatory effect only on Km-ChgH in hermaphrodites. Tamoxifen, an antagonist of the estrogen receptor showed no effect on expression of Chg genes in either of the gender types of K. marmoratus. These findings indicate that Km-Chg genes would be associated with estrogen and measurement of their expression would serve as a surrogate biomarker of exposure to environmental EDCs.


Assuntos
Proteínas do Ovo/metabolismo , Disruptores Endócrinos/toxicidade , Estrogênios/toxicidade , Peixes Listrados/metabolismo , Fígado/efeitos dos fármacos , Precursores de Proteínas/metabolismo , Animais , Compostos Benzidrílicos , Biomarcadores/metabolismo , Clonagem Molecular , Proteínas do Ovo/genética , Monitoramento Ambiental/métodos , Estradiol/toxicidade , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Organismos Hermafroditas , Peixes Listrados/embriologia , Peixes Listrados/genética , Fígado/embriologia , Fígado/metabolismo , Masculino , Fenóis/toxicidade , Precursores de Proteínas/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Processos de Determinação Sexual , Tamoxifeno/toxicidade , Fatores de Tempo
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