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1.
BMC Genomics ; 22(1): 658, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34517816

RESUMO

BACKGROUND: Zebrafish is a popular animal model used for high-throughput screening of chemical hazards, however, investigations of transcriptomic mechanisms of toxicity are still needed. Here, our goal was to identify genes and biological pathways that Aryl Hydrocarbon Receptor 2 (AHR2) Activators and flame retardant chemicals (FRCs) alter in developing zebrafish. Taking advantage of a compendium of phenotypically-anchored RNA sequencing data collected from 48-h post fertilization (hpf) zebrafish, we inferred a co-expression network that grouped genes based on their transcriptional response. RESULTS: Genes responding to the FRCs and AHR2 Activators localized to distinct regions of the network, with FRCs inducing a broader response related to neurobehavior. AHR2 Activators centered in one region related to chemical stress responses. We also discovered several highly co-expressed genes in this module, including cyp1a, and we subsequently show that these genes are definitively within the AHR2 signaling pathway. Systematic removal of the two chemical types from the data, and analysis of network changes identified neurogenesis associated with FRCs, and regulation of vascular development associated with both chemical classes. We also identified highly connected genes responding specifically to each class that are potential biomarkers of exposure. CONCLUSIONS: Overall, we created the first zebrafish chemical-specific gene co-expression network illuminating how chemicals alter the transcriptome relative to each other. In addition to our conclusions regarding FRCs and AHR2 Activators, our network can be leveraged by other studies investigating chemical mechanisms of toxicity.


Assuntos
Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Sequência de Bases , Embrião não Mamífero/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Transcriptoma , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética
2.
Life Sci ; 283: 119864, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34358548

RESUMO

AIMS: The study examined that morin as possible antioxidant and neuroprotective due to oxidative stress (H2O2) in zebrafish larval model. MATERIALS AND METHODS: Zebrafish larvae were induced with oxidative stress using H2O2 at 1 mM; their behavioural changes were assessed through partition preference and horizontal compartment test. The head section without eyes and yolk sac of zebrafish larvae were employed for enzyme assays such as SOD, CAT, Thiobarbituric acid reactive substances assay, reduced glutathione, glutathione peroxidase activity, glutathione S transferase, Acetylcholinesterase activity and nitrate levels. Also, intracellular ROS and apoptosis in larval head was detected by DCFDA and acridine orange staining followed by gene expression studies. KEY FINDINGS: Morin exposure was not harmful to the larvae at concentration between 20 and 60 µM, but it caused non-lethal deformity between 80 and 100 µM. In the partition test, zebrafish embryos treated with H2O2 showed cognitive impairment, whereas the morin-treated groups showed an improved behavioural activity. The study also found that restoring antioxidant enzymes and reduced lipid peroxidation which had a neuroprotective impact. Inhibition of NO overproduction and increased AChE activity were also shown to reduce the neuronal damage. Apoptosis and intracellular ROS levels were reduced in larvae when it was co-incubated with morin. Morin treatment up regulated the antioxidant enzymes against oxidative stress. SIGNIFICANCE: Morin provides protection against H2O2 induced oxidative stress through a cellular antioxidant defence mechanism by up-regulating gene expression, thus increasing the antioxidant activity at cellular or organismal stage.


Assuntos
Antioxidantes/farmacologia , Embrião não Mamífero/metabolismo , Flavonoides/farmacologia , Síndromes Neurotóxicas , Estresse Oxidativo/efeitos dos fármacos , Peixe-Zebra/embriologia , Animais , Embrião não Mamífero/patologia , Peróxido de Hidrogênio/efeitos adversos , Peróxido de Hidrogênio/farmacologia , Síndromes Neurotóxicas/tratamento farmacológico , Síndromes Neurotóxicas/embriologia , Síndromes Neurotóxicas/patologia
3.
Biomed Pharmacother ; 138: 111521, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34311525

RESUMO

Euphorbiae pekinensis Radix (EP) is effective in treating various diseases, but it's toxicity is a major obstacle in use in clinical. Although EP was processed with vinegar to reduce it's toxicity, the detailed mechanism of toxicity in EP have not been clearly delineated. This study investigate the toxicity attenuation-mechanism of Euphorbiae pekinensis after being processed with vinegar (VEP) and the toxic mechanism of four compounds from EP on zebrafish embryos. The contents of four compounds decreased obviously in VEP. Correspondingly, slower development on embryos can be seen as some symptoms like reduction of heart rate, liver area and gastrointestinal peristalsis after exposed to the compounds. Some obvious pathological signals such as pericardial edema and yolk sac edema were observed. Furthermore, the compounds could increase the contents of MDA and GSH-PX and induce oxidative damage by inhibiting the activity of SOD. Also, four compounds could provoke apoptosis by up-regulating the expression level of p53, MDM2, Bax, Bcl-2 and activating the activity of caspase-3, caspase-9. In conclusion, the four compounds play an important role in the toxicity attenuation effects of VEP, which may be related to the apoptosis induction and oxidative damage. This would contribute to the clinical application and further toxicity-reduction mechanism research.


Assuntos
Euphorbia/toxicidade , Trato Gastrointestinal/efeitos dos fármacos , Coração/efeitos dos fármacos , Fígado/efeitos dos fármacos , Compostos Fitoquímicos/toxicidade , Extratos Vegetais/toxicidade , Peixe-Zebra/embriologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Cardiotoxicidade , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Embrião não Mamífero/patologia , Euphorbia/química , Trato Gastrointestinal/embriologia , Trato Gastrointestinal/metabolismo , Coração/embriologia , Fígado/embriologia , Fígado/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
4.
Nat Commun ; 12(1): 4504, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301936

RESUMO

Genes are expressed in stochastic transcriptional bursts linked to alternating active and inactive promoter states. A major challenge in transcription is understanding how promoter composition dictates bursting, particularly in multicellular organisms. We investigate two key Drosophila developmental promoter motifs, the TATA box (TATA) and the Initiator (INR). Using live imaging in Drosophila embryos and new computational methods, we demonstrate that bursting occurs on multiple timescales ranging from seconds to minutes. TATA-containing promoters and INR-containing promoters exhibit distinct dynamics, with one or two separate rate-limiting steps respectively. A TATA box is associated with long active states, high rates of polymerase initiation, and short-lived, infrequent inactive states. In contrast, the INR motif leads to two inactive states, one of which relates to promoter-proximal polymerase pausing. Surprisingly, the model suggests pausing is not obligatory, but occurs stochastically for a subset of polymerases. Overall, our results provide a rationale for promoter switching during zygotic genome activation.


Assuntos
Drosophila melanogaster/genética , Embrião não Mamífero/metabolismo , Regiões Promotoras Genéticas/genética , TATA Box/genética , Imagem com Lapso de Tempo/métodos , Transcrição Genética/genética , Algoritmos , Animais , Animais Geneticamente Modificados , Drosophila melanogaster/embriologia , Drosophila melanogaster/metabolismo , Embrião não Mamífero/embriologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Cinética , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microscopia Confocal , Modelos Teóricos
5.
Nat Commun ; 12(1): 4484, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301940

RESUMO

Reactive oxygen species (ROS) represent a by-product of metabolism and their excess is toxic for hematopoietic stem and progenitor cells (HSPCs). During embryogenesis, a small number of HSPCs are produced from the hemogenic endothelium, before they colonize a transient organ where they expand, for example the fetal liver in mammals. In this study, we use zebrafish to understand the molecular mechanisms that are important in the caudal hematopoietic tissue (equivalent to the mammalian fetal liver) to promote HSPC expansion. High levels of ROS are deleterious for HSPCs in this niche, however this is rescued by addition of antioxidants. We show that Cx41.8 is important to lower ROS levels in HSPCs. We also demonstrate a new role for ifi30, known to be involved in the immune response. In the hematopoietic niche, Ifi30 can recycle oxidized glutathione to allow HSPCs to dampen their levels of ROS, a role that could be conserved in human fetal liver.


Assuntos
Conexinas/genética , Células-Tronco Hematopoéticas/metabolismo , Estresse Oxidativo , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Transdução de Sinais/genética , Nicho de Células-Tronco , Proteínas de Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Conexinas/metabolismo , Embrião não Mamífero/citologia , Embrião não Mamífero/embriologia , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Hematopoéticas/citologia , Humanos , Microscopia Confocal , Mutação , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Imagem com Lapso de Tempo/métodos , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
6.
Sci Total Environ ; 796: 148780, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34280625

RESUMO

Aquaculture plays a pivotal role in covering dietary animal protein demands and restocking endangered fish populations. However, high mortality takes place at the earliest life stages: prior and immediately after hatching. Improving growth and health parameters by immunostimulants is widely used in older fish, but rarely studied in larvae. Fulvic acids (FAs) are natural substances found in soil and water. Using zebrafish as a model organism, we evaluated the effects of exposure to a FA at concentrations ranging from 1 to 500 mg C/L (mg dissolved organic carbon per liter) on embryonic development. Furthermore, the concentration of reactive oxygen species (ROS) inside the larvae as well as the molecular mechanisms involved in growth, immune response, and antioxidative protection were determined at 5, 50, and 500 mg C/L. 20 to 200 mg C/L accelerated the hatching, which was mediated by increased expression of ifg-1, gh, and he1-α. Furthermore, lyz and mpx were significantly increased at 5 and 50 mg C/L. A concentration of 500 mg C/L induced genes involved in the protection against ROS (nrf-2, keap-1, cat, sod-1), increased the concentration of ROS inside the larvae and caused tissue damage and mortality. Interestingly, 50 mg C/L activated ROS protection as well (nrf-2, sod-2), while no increase of ROS was found in the larvae. Our results show, that FA at low to medium concentrations can increase the health of larvae, but becomes detrimental at higher concentrations.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Antioxidantes/metabolismo , Benzopiranos , Gatos , Embrião não Mamífero/metabolismo , Imunidade Inata , Larva , Estresse Oxidativo , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
7.
Sci Total Environ ; 796: 149047, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34280629

RESUMO

4-Epianhydrotetracycline (4-EATC) is a major intermediate product of tetracycline during its degradation progress in the natural environment, which is frequently detected in aquatic environments and poses a potential threat to aquatic organisms. In the present study, the ecotoxicity of 4-EATC have been studied from the perspective of oxidative stress by using zebrafish embryos. After 96 h exposure, the reactive oxygen species (ROS) levels, malondialdehyde (MDA) concentrations and protein carbonyl (PC) contents in zebrafish embryos in the lower-concentration 4-EATC treatment groups (1.25 mg/L and 2.50 mg/L) showed no significant differences compared with the negative control group. However, the total superoxide dismutase (SOD) activity was increased significantly. After exposed to the higher-concentration of 4-EATC (5.00, 10.0 and 20.0 mg/L) resulted in a significant increase in ROS levels, MDA concentrations and PC contents, in contrast, a significant decrease in SOD activities. The results indicate that exposure to high concentrations of 4-EATC (5.00, 10.0 and 20.0 mg/L) could disrupt the redox equilibrium in zebrafish embryos, leading to the occurrence of oxidative damage. Apoptosis of the embryonic cells could be induced by 4-EATC exposure at different concentration and the rate of apoptosis enhanced with the increase of 4-EATC concentration. The pericardium was the most frequent site of apoptosis. The present study points out that more attention should be paid to the potential ecological risks of antibiotic degradation products.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Embrião não Mamífero/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Tetraciclinas , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo
8.
Ecotoxicol Environ Saf ; 222: 112514, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34280841

RESUMO

Pendimethalin (PND) is one of the best sellers of selective herbicide in the world and has been frequently detected in the water. However, little is known about its effects on cardiac development. In this study, we used zebrafish to investigate the developmental and cardiac toxicity of PND. We exposed the zebrafish embryos with a serial of concentrations at 3, 4, and 5 mg/L at 5.5-72 h post-fertilization (hpf). We found that PND exposure can reduce the heart rate, survival rate, and body length of zebrafish embryos. Furthermore, we identified many malformations including pericardial and yolk sac edema, spinal deformity, and cardiac looping abnormality. In addition, PND increased the expression of reactive oxygen species and malondialdehyde and reduced the activity of superoxide dismutase (Antioxidant enzymes); We examined the expression of cardiac development-related genes and the apoptosis markers, and found changes of the following marker: vmhc, nppa, tbx5a, nkx2.5, gata4, tbx2b and FoxO1, bax, bcl-2, p53, casp-9, casp-3. Our data showed that activation of Wnt pathway can rescue the cardiac abnormalities caused by PND. Our results provided new evidence for the toxicity of PND and suggested that the PND residual should be treated as a hazard in the environment.


Assuntos
Embrião não Mamífero , Peixe-Zebra , Compostos de Anilina , Animais , Apoptose , Cardiotoxicidade/metabolismo , Embrião não Mamífero/metabolismo , Estresse Oxidativo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
9.
Environ Pollut ; 287: 117649, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34182397

RESUMO

Gabapentin-lactam (GBP-L) is a transformation product (TP) of gabapentin (GBP), a widely used anti-epileptic pharmaceutical. Due to its high persistence, GBP-L has been frequently detected in the surface water. However, the effects of GBP-L on aquatic organisms have not been thoroughly investigated. In the present study, zebrafish (Danio rerio) embryos as a model organism were used to study the impacts of GBP-L in terms of embryos LC50, spontaneous movement at 24 hpf (hours post fertilization), heartbeat rates at 48 hpf, and body length at 72 hpf, with the concentrations of GBP-L down to 0.01 µg/L, covering its environmental concentrations. Various biomarkers from nervous, antioxidant and immune systems of zebrafish larvae were analyzed, including acetylcholinesterase, acetylcholine, dopamine, gamma-aminobutyric acid, superoxide dismutase, catalase, glutathione S-transferase, C reactive protein, and lysozyme, to assess its toxicity on these systems. RT-qPCR was then used to further verify the results and explain the toxicological mechanism at the gene level. The results demonstrated that GBP-L is much more toxic than its parent compound, and could lead to adverse impacts on the aquatic organisms even at every low concentrations.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Compostos Aza , Embrião não Mamífero/metabolismo , Larva , Estresse Oxidativo , Compostos de Espiro , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
10.
Development ; 148(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34100067

RESUMO

Cells of the same type can be generated by distinct cellular lineages that originate in different parts of the developing embryo ('lineage convergence'). Several Caenorhabditis elegans neuron classes composed of left/right or radially symmetric class members display such lineage convergence. We show here that the C. elegans Atonal homolog lin-32 is differentially expressed in neuronal lineages that give rise to left/right or radially symmetric class members. Loss of lin-32 results in the selective loss of the expression of pan-neuronal markers and terminal selector-type transcription factors that confer neuron class-specific features. Another basic helix-loop-helix (bHLH) gene, the Achaete-Scute homolog hlh-14, is expressed in a mirror image pattern relative to lin-32 and is required to induce neuronal identity and terminal selector expression on the contralateral side of the animal. These findings demonstrate that distinct lineage histories converge via different bHLH factors at the level of induction of terminal selector identity determinants, which thus serve as integrators of distinct lineage histories. We also describe neuron-to-neuron identity transformations in lin-32 mutants, which we propose to also be the result of misregulation of terminal selector gene expression.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Linhagem da Célula/fisiologia , Neurônios/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Diferenciação Celular , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Transcrição
11.
Environ Pollut ; 285: 117323, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34091267

RESUMO

Evaluation of the toxicity of pesticide residues on non-target organisms in the ecosystem is an important part of pesticide environmental risk assessment. Flupyradifurone is a new type of butenolide insecticide produced by Bayer, who claims it to be "low toxic" to non-target organisms in the environment. However, there is little evidence in the literature to show how flupyradifurone affects aquatic organism development. In the current study, zebrafish embryos were treated with 0.1, 0.15, and 0.2 mg/mL of flupyradifurone within 6.0-72 h past fertilization (hpf). We found that the half-lethal concentration (LC50) of flupyradifurone for zebrafish embryos at 96 hpf was 0.21 mg/mL. Flupyradifurone decreases the heart rate, survival rate, and body length of zebrafish embryos. The flupyradifurone treatment also led to the failure of heart looping, and pericardial edema. Moreover, flupyradifurone increased the level of reactive oxygen species (ROS) and decreased the enzymatic catalysis of catalase (CAT) and superoxide dismutase (SOD). Alterations were induced in the transcription of apoptosis-related genes (bcl-2, bax, bax/bcl-2, p53 and caspase-9) and the heart development-related genes (gata4, myh6, nkx2.5, nppa, tbx2b, tbx5 and vmhc). In the current study, new evidences have been provided regarding the toxic effects of flupyradifurone and the risk of its residues in agricultural products and the environment.


Assuntos
Embrião não Mamífero , Peixe-Zebra , 4-Butirolactona/análogos & derivados , Animais , Apoptose , Ecossistema , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário , Estresse Oxidativo , Piridinas
12.
Commun Biol ; 4(1): 680, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34083748

RESUMO

Genetic engineering techniques have contributed to the now widespread use of zebrafish to investigate gene function, but zebrafish-based human disease studies, and particularly for neurological disorders, are limited. Here we used CRISPR-Cas9 to generate 40 single-gene mutant zebrafish lines representing catastrophic childhood epilepsies. We evaluated larval phenotypes using electrophysiological, behavioral, neuro-anatomical, survival and pharmacological assays. Local field potential recordings (LFP) were used to screen ∼3300 larvae. Phenotypes with unprovoked electrographic seizure activity (i.e., epilepsy) were identified in zebrafish lines for 8 genes; ARX, EEF1A, GABRB3, GRIN1, PNPO, SCN1A, STRADA and STXBP1. We also created an open-source database containing sequencing information, survival curves, behavioral profiles and representative electrophysiology data. We offer all zebrafish lines as a resource to the neuroscience community and envision them as a starting point for further functional analysis and/or identification of new therapies.


Assuntos
Modelos Animais de Doenças , Embrião não Mamífero/metabolismo , Epilepsia/genética , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Criança , Embrião não Mamífero/citologia , Embrião não Mamífero/embriologia , Epilepsia/patologia , Epilepsia/fisiopatologia , Expressão Gênica , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Larva/genética , Mutação , Fenótipo , Análise de Sobrevida , Sequenciamento Completo do Exoma/métodos , Peixe-Zebra/embriologia
13.
Development ; 148(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34100063

RESUMO

Zic-r.a, a maternal transcription factor, specifies posterior fate in ascidian embryos. However, its direct target, Tbx6-r.b, does not contain typical Zic-r.a-binding sites in its regulatory region. Using an in vitro selection assay, we found that Zic-r.a binds to sites dissimilar to the canonical motif, by which it activates Tbx6-r.b in a sub-lineage of muscle cells. These sites with non-canonical motifs have weak affinity for Zic-r.a; therefore, it activates Tbx6-r.b only in cells expressing Zic-r.a abundantly. Meanwhile, we found that Zic-r.a expressed zygotically in late embryos activates neural genes through canonical sites. Because different zinc-finger domains of Zic-r.a are important for driving reporters with canonical and non-canonical sites, it is likely that the non-canonical motif is not a divergent version of the canonical motif. In other words, our data indicate that the non-canonical motif represents a motif distinct from the canonical motif. Thus, Zic-r.a recognizes two distinct motifs to activate two sets of genes at two timepoints in development. This article has an associated 'The people behind the papers' interview.


Assuntos
Linhagem da Célula/genética , Linhagem da Célula/fisiologia , Expressão Gênica , Dedos de Zinco/genética , Animais , Sítios de Ligação , Ciona intestinalis/genética , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas com Domínio T/metabolismo , Fatores de Transcrição/metabolismo , Urocordados/embriologia , Urocordados/genética
14.
Nat Commun ; 12(1): 3358, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099733

RESUMO

Early stages of embryogenesis depend on subcellular localization and transport of maternal mRNA. However, systematic analysis of these processes is hindered by a lack of spatio-temporal information in single-cell RNA sequencing. Here, we combine spatially-resolved transcriptomics and single-cell RNA labeling to perform a spatio-temporal analysis of the transcriptome during early zebrafish development. We measure spatial localization of mRNA molecules within the one-cell stage embryo, which allows us to identify a class of mRNAs that are specifically localized at an extraembryonic position, the vegetal pole. Furthermore, we establish a method for high-throughput single-cell RNA labeling in early zebrafish embryos, which enables us to follow the fate of individual maternal transcripts until gastrulation. This approach reveals that many localized transcripts are specifically transported to the primordial germ cells. Finally, we acquire spatial transcriptomes of two xenopus species and compare evolutionary conservation of localized genes as well as enriched sequence motifs.


Assuntos
Rastreamento de Células/métodos , Embrião não Mamífero/metabolismo , RNA Mensageiro/genética , Transcriptoma/genética , Peixe-Zebra/genética , Animais , Embrião não Mamífero/citologia , Embrião não Mamífero/embriologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Oócitos/citologia , Oócitos/metabolismo , RNA Mensageiro/metabolismo , Análise de Célula Única/métodos , Análise Espaço-Temporal , Especificidade da Espécie , Xenopus/embriologia , Xenopus/genética , Xenopus laevis/embriologia , Xenopus laevis/genética , Peixe-Zebra/embriologia
15.
Development ; 148(13)2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34164654

RESUMO

Understanding the mechanisms of embryonic cell cycles is a central goal of developmental biology, as the regulation of the cell cycle must be closely coordinated with other events during early embryogenesis. Quantitative imaging approaches have recently begun to reveal how the cell cycle oscillator is controlled in space and time, and how it is integrated with mechanical signals to drive morphogenesis. Here, we discuss how the Drosophila embryo has served as an excellent model for addressing the molecular and physical mechanisms of embryonic cell cycles, with comparisons to other model systems to highlight conserved and species-specific mechanisms. We describe how the rapid cleavage divisions characteristic of most metazoan embryos require chemical waves and cytoplasmic flows to coordinate morphogenesis across the large expanse of the embryo. We also outline how, in the late cleavage divisions, the cell cycle is inter-regulated with the activation of gene expression to ensure a reliable maternal-to-zygotic transition. Finally, we discuss how precise transcriptional regulation of the timing of mitosis ensures that tissue morphogenesis and cell proliferation are tightly controlled during gastrulation.


Assuntos
Pontos de Checagem do Ciclo Celular/fisiologia , Drosophila/embriologia , Desenvolvimento Embrionário/fisiologia , Animais , Proteína Quinase CDC2 , Ciclo Celular/genética , Proteínas de Drosophila , Embrião de Mamíferos , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Mitose , Morfogênese , Xenopus/embriologia , Zigoto/metabolismo
16.
J Vet Med Sci ; 83(7): 1050-1058, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34024870

RESUMO

We reported the involvement of oxidative stress and prostaglandins including thromboxane and prostacyclin in pre-cardiac edema (early edema) caused by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). While the involvement of oxidative stress in TCDD-induced toxicity has been frequently reported, the mechanism of its action is still unclear. In the present study, oxidative stress inducers including paraquat, hydrogen peroxide (H2O2) and rotenone augmented early edema (edema) induced by a low concentration of TCDD (0.1 ppb) at 55 hr post fertilization (hpf), while each of them alone did not cause edema. Edema caused by TCDD plus oxidative stress inducers was almost abolished by antioxidants, an antagonist for thromboxane receptor (ICI-192,605) and an agonist for prostacyclin receptor (beraprost), suggesting that the site of action of these inducers was in the regular signaling pathway after activation of aryl hydrocarbon receptor type 2 (AHR2) by TCDD. Oxidative stress inducers also enhanced edema caused by an agonist for the thromboxane receptor (U46619), and the enhancement was also inhibited by antioxidants. Sulforaphane and auranofin, activators of Nrf2 that is a master regulator of anti-oxidative response, did not affect U46619-evoked edema but almost abolished TCDD-induced edema and potentiation by paraquat in both TCDD- and U46619-induced edema. Taken together, the results suggest that oxidative stress augments pre-cardiac edema caused by TCDD via activation of thromboxane receptor-mediated signaling in developing zebrafish. As paraquat and other oxidative stress inducers used also are environmental pollutants, interaction between dioxin-like compounds and exogenous source of oxidative stress should also be considered.


Assuntos
Dibenzodioxinas Policloradas , Peixe-Zebra , Animais , Edema Cardíaco/metabolismo , Edema Cardíaco/veterinária , Embrião não Mamífero/metabolismo , Peróxido de Hidrogênio/metabolismo , Larva/metabolismo , Estresse Oxidativo , Dibenzodioxinas Policloradas/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo , Proteínas de Peixe-Zebra/metabolismo
17.
Science ; 372(6543): 716-721, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33986176

RESUMO

Transcription and metabolism both influence cell function, but dedicated transcriptional control of metabolic pathways that regulate cell fate has rarely been defined. We discovered, using a chemical suppressor screen, that inhibition of the pyrimidine biosynthesis enzyme dihydroorotate dehydrogenase (DHODH) rescues erythroid differentiation in bloodless zebrafish moonshine (mon) mutant embryos defective for transcriptional intermediary factor 1 gamma (tif1γ). This rescue depends on the functional link of DHODH to mitochondrial respiration. The transcription elongation factor TIF1γ directly controls coenzyme Q (CoQ) synthesis gene expression. Upon tif1γ loss, CoQ levels are reduced, and a high succinate/α-ketoglutarate ratio leads to increased histone methylation. A CoQ analog rescues mon's bloodless phenotype. These results demonstrate that mitochondrial metabolism is a key output of a lineage transcription factor that drives cell fate decisions in the early blood lineage.


Assuntos
Eritropoese , Mitocôndrias/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Genética , Proteínas de Peixe-Zebra/metabolismo , Animais , Ciclo do Ácido Cítrico , Metilação de DNA , Transporte de Elétrons , Embrião não Mamífero/metabolismo , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica , Histonas/metabolismo , Leflunomida/farmacologia , Redes e Vias Metabólicas , Metilação , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Consumo de Oxigênio , Fatores de Transcrição/genética , Ubiquinona/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
18.
Food Chem ; 360: 129999, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33989880

RESUMO

In this study, cherry fruits and petioles from six ancient Italian Prunus avium L. varieties (Ferrovia, Capellina, Morellina, Ciambellana, Napoletana, and Bianca), were compared by chemical and bioinformatic analyses and evaluated for their antiangiogenic activity. The highest levels of total phenols and flavonoids were found in Napoletana petioles, and Morellina and Capellina fruits. HPLC-PDA-MS analyses showed similar phenolic profiles for all fruit extracts, with cyanidin-3-O-rutinoside, flavonols glycosides, and quinic acid derivatives as major components. Flavonoid glycosides were found in all petiole extracts, while proanthocyanidins B type were predominant in Capellina, Napoletana and Bianca. Accordingly to their higher polyphenolic content, petiole extracts exhibited stronger radical scavenging activity compared to the fruits. The best antiangiogenic response was exhibited by Morellina, Ferrovia, and Ciambellana petiole extracts, and by Ferrovia, Morellina, and Capellina fruit extracts; by bioinformatic studies rutin and cyanidin 3-O-rutinoside were recognised as the best candidate bioactive compounds. In conclusion, sweet cherry varietes were confirmed as valuable sources of phenols, showing also potential angiomodulator properties.


Assuntos
Inibidores da Angiogênese/análise , Extratos Vegetais/química , Prunus avium/química , Fosfatase Alcalina/metabolismo , Inibidores da Angiogênese/farmacologia , Animais , Antocianinas/análise , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Embrião não Mamífero/diagnóstico por imagem , Embrião não Mamífero/metabolismo , Flavonoides/análise , Frutas/química , Frutas/metabolismo , Itália , Fenóis/análise , Extratos Vegetais/farmacologia , Prunus avium/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo
19.
Aquat Toxicol ; 236: 105872, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34052719

RESUMO

Aluminium is a non-essential metal and potentially toxic to organisms whose environmental concentration increases due to pollution. In our previous studies, the behavioral changes induced by aluminium were already shown on zebrafish, a model organism widely used for ecotoxicology screening. To examine in depth the knowledge about the toxicity mechanism induced by this metal, zebrafish embryos, at 6 hpf, have been exposed to 50, 100 and 200 µM of AlCl3 for 72 h. Phenotypic alterations, apoptosis and oxidative stress responses have been assessed by evaluations of antioxidant defence and changes in metabolism at the end of treatment. The mRNA expression level of c-fos, appa and appb as marker genes of neural development and function were analyzed by qPCR for the highest used concentration. The data showed that aluminium significantly affected the development of zebrafish inducing morphological alterations and cell death. The oxidative state of larvae was altered, although the formation of reactive oxygen species and the levels of metallothioneins, and the activity of some antioxidant enzymes, decreased at the maximum concentration tested. In addition, at this concentration, the expression of the evaluated genes increased. The comprehensive information obtained gives a realistic snapshot of the aluminium toxicity and provides new information on the mechanism of action of this metal.


Assuntos
Alumínio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Apoptose , Dano ao DNA , Embrião não Mamífero/metabolismo , Larva/metabolismo , Oxirredução , Estresse Oxidativo/genética , Espécies Reativas de Oxigênio/metabolismo , Peixe-Zebra/metabolismo
20.
Res Vet Sci ; 137: 68-76, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33933710

RESUMO

In this study, the effects of Goose parvovirus (GPV) infection as well as the possible role of NS1 protein on apoptosis induction in goose embryo fibroblast (GEF) cells were examined. Flow cytometry analysis and TUNEL assays revealed that GPV infection and NS1 transfection induced significant apoptosis in GEF cells compared to what was observed in mock-infected cells. Interestingly, the increase in the rate of apoptosis detected in GPV-infected GEFs was accompanied by an increased viral load in the cells. In addition, the apoptotic pathway was mediated by apoptosis-inducing factors (AIFs) and internal factors that influence the release of AIFs. The results indicated that the mitochondrial membrane potential was decreased, and AIF expression was increased in the nucleus (P < 0.01). Reactive oxygen species (ROS) increased gradually within 48 h (P < 0.001). Cathepsin D activities were also increased (P < 0.05). The results demonstrated that the AIF-mediated pathway is a new mitochondrial apoptotic pathway and that mitochondrial depolarization, ROS content, and cathepsin D activities are the key factors influencing apoptosis in GEF cells.


Assuntos
Fibroblastos/virologia , Gansos/embriologia , Parvovirinae/patogenicidade , Proteínas não Estruturais Virais/farmacologia , Animais , Apoptose , Fator de Indução de Apoptose/metabolismo , Fator de Indução de Apoptose/farmacologia , Catepsina D/metabolismo , Morte Celular , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Mitocôndrias/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo
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