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1.
BMC Ecol Evol ; 21(1): 156, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34372763

RESUMO

BACKGROUND: Synthetic gene drive technologies aim to spread transgenic constructs into wild populations even when they impose organismal fitness disadvantages. The extraordinary diversity of plausible drive mechanisms and the range of selective parameters they may encounter makes it very difficult to convey their relative predicted properties, particularly where multiple approaches are combined. The sheer number of published manuscripts in this field, experimental and theoretical, the numerous techniques resulting in an explosion in the gene drive vocabulary hinder the regulators' point of view. We address this concern by defining a simplified parameter based language of synthetic drives. RESULTS: Employing the classical population dynamics approach, we show that different drive construct (replacement) mechanisms can be condensed and evaluated on an equal footing even where they incorporate multiple replacement drives approaches. Using a common language, it is then possible to compare various model properties, a task desired by regulators and policymakers. The generalization allows us to extend the study of the invasion dynamics of replacement drives analytically and, in a spatial setting, the resilience of the released drive constructs. The derived framework is available as a standalone tool. CONCLUSION: Besides comparing available drive constructs, our tool is also useful for educational purpose. Users can also explore the evolutionary dynamics of future hypothetical combination drive scenarios. Thus, our results appraise the properties and robustness of drives and provide an intuitive and objective way for risk assessment, informing policies, and enhancing public engagement with proposed and future gene drive approaches.


Assuntos
Tecnologia de Impulso Genético , Animais , Animais Geneticamente Modificados , Dinâmica Populacional
2.
Int J Mol Sci ; 22(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34445163

RESUMO

Mammalian cells utilize a wide spectrum of pathways to antagonize the viral replication. These pathways are typically regulated by antiviral proteins and can be constitutively expressed but also exacerbated by interferon induction. A myriad of interferon-stimulated genes (ISGs) have been identified in mounting broad-spectrum antiviral responses. Members of the interferon-induced transmembrane (IFITM) family of proteins are unique among these ISGs due to their ability to prevent virus entry through the lipid bilayer into the cell. In the current study, we generated transgenic chickens that constitutively and stably expressed chicken IFITM1 (chIFITM1) using the avian sarcoma-leukosis virus (RCAS)-based gene transfer system. The challenged transgenic chicks with clinical dose 104 egg infective dose 50 (EID50) of highly pathogenic avian influenza virus (HPAIV) subtype H5N1 (clade 2.2.1.2) showed 100% protection and significant infection tolerance. Although challenged transgenic chicks displayed 60% protection against challenge with the sub-lethal dose (EID50 105), the transgenic chicks showed delayed clinical symptoms, reduced virus shedding, and reduced histopathologic alterations compared to non-transgenic challenged control chickens. These finding indicate that the sterile defense against H5N1 HPAIV offered by the stable expression of chIFITM1 is inadequate; however, the clinical outcome can be substantially ameliorated. In conclusion, chIFITM proteins can inhibit influenza virus replication that can infect various host species and could be a crucial barrier against zoonotic infections.


Assuntos
Antígenos de Diferenciação/genética , Proteínas Aviárias/genética , Galinhas/genética , Virus da Influenza A Subtipo H5N1/fisiologia , Influenza Aviária/genética , Animais , Animais Geneticamente Modificados/genética , Galinhas/virologia , Técnicas de Transferência de Genes , Influenza Aviária/patologia , Influenza Aviária/virologia
3.
Ecotoxicol Environ Saf ; 223: 112557, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343899

RESUMO

The impact of transgenic crops on non-target organisms is a key aspect of environmental safety assessment to transgenic crops. In the present study, we fed two snail species, Bradybaena (Acusta) ravida (B. ravida) and Bradybaena similaris (Ferussac)(B. similaris), with the leaves of transgenic Bt cotton Zhong 30 (Z30) and control cotton, its parent line zhong 16 (Z16), to assess the environmental safety of Bt cotton to common non-target organisms in the field. Survival, body weight, shell diameter, helix number, reproduction rate, superoxide dismutase (SOD) activity and Bt protein concentration in snails were monitored in 15 days and 180 days experiments. We also monitored the population dynamics of B. ravida and B. similaris in Z30 and Z16 cotton fields for two successive years. Compared to the snails fed on the control cotton Z16, there was no significant difference in survival, growth, reproduction, and SOD activity on Bt cotton Z30. Bt protein concentrations were significantly between different treatments, and Bt protein residues were only detected in the feces of the Z30 treatment. According to the field data, the number of B. ravida and B. similaris fluctuated considerably across seasons over the entire cotton-growing season; however, there were no significant differences between the Bt and control cotton fields at similar time. As the results showed, in our experiments, Bt cotton Z30 had no adverse effects on the two snail species, both in the laboratory and in the fields.


Assuntos
Produtos Agrícolas , Caramujos , Animais , Animais Geneticamente Modificados , Proteínas de Bactérias/genética , Endotoxinas/genética , Endotoxinas/toxicidade , Gossypium/genética , Proteínas Hemolisinas/genética , Plantas Geneticamente Modificadas , Reprodução , Caramujos/genética
4.
Nat Commun ; 12(1): 5043, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34413292

RESUMO

Skeletal muscle has a remarkable ability to regenerate owing to its resident stem cells (also called satellite cells, SCs). SCs are normally quiescent; when stimulated by damage, they activate and expand to form new fibers. The mechanisms underlying SC proliferative progression remain poorly understood. Here we show that DHX36, a helicase that unwinds RNA G-quadruplex (rG4) structures, is essential for muscle regeneration by regulating SC expansion. DHX36 (initially named RHAU) is barely expressed at quiescence but is highly induced during SC activation and proliferation. Inducible deletion of Dhx36 in adult SCs causes defective proliferation and muscle regeneration after damage. System-wide mapping in proliferating SCs reveals DHX36 binding predominantly to rG4 structures at various regions of mRNAs, while integrated polysome profiling shows that DHX36 promotes mRNA translation via 5'-untranslated region (UTR) rG4 binding. Furthermore, we demonstrate that DHX36 specifically regulates the translation of Gnai2 mRNA by unwinding its 5' UTR rG4 structures and identify GNAI2 as a downstream effector of DHX36 for SC expansion. Altogether, our findings uncover DHX36 as an indispensable post-transcriptional regulator of SC function and muscle regeneration acting through binding and unwinding rG4 structures at 5' UTR of target mRNAs.


Assuntos
Regiões 5' não Traduzidas , RNA Helicases DEAD-box/metabolismo , Quadruplex G , Músculos/citologia , Regeneração/fisiologia , Células-Tronco/citologia , Animais , Animais Geneticamente Modificados , Células Cultivadas , Modelos Animais de Doenças , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/metabolismo , Regulação da Expressão Gênica , Humanos , Camundongos , Músculos/metabolismo , Mioblastos/metabolismo , Polirribossomos/metabolismo , Biossíntese de Proteínas , RNA Mensageiro/genética , Células-Tronco/metabolismo
5.
Nat Commun ; 12(1): 5041, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34413299

RESUMO

In vivo reprogramming provokes a wide range of cell fate conversion. Here, we discover that in vivo induction of higher levels of OSKM in mouse somatic cells leads to increased expression of primordial germ cell (PGC)-related genes and provokes genome-wide erasure of genomic imprinting, which takes place exclusively in PGCs. Moreover, the in vivo OSKM reprogramming results in development of cancer that resembles human germ cell tumors. Like a subgroup of germ cell tumors, propagated tumor cells can differentiate into trophoblasts. Moreover, these tumor cells give rise to induced pluripotent stem cells (iPSCs) with expanded differentiation potential into trophoblasts. Remarkably, the tumor-derived iPSCs are able to contribute to non-neoplastic somatic cells in adult mice. Mechanistically, DMRT1, which is expressed in PGCs, drives the reprogramming and propagation of the tumor cells in vivo. Furthermore, the DMRT1-related epigenetic landscape is associated with trophoblast competence of the reprogrammed cells and provides a therapeutic target for germ cell tumors. These results reveal an unappreciated route for somatic cell reprogramming and underscore the impact of reprogramming in development of germ cell tumors.


Assuntos
Células-Tronco Pluripotentes Induzidas/patologia , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias/patologia , Fatores de Transcrição/metabolismo , Animais , Animais Geneticamente Modificados , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Células Cultivadas , Reprogramação Celular/fisiologia , Epigênese Genética , Feminino , Impressão Genômica , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Embrionárias de Células Germinativas/metabolismo , Fatores de Transcrição/genética
6.
Nat Commun ; 12(1): 5040, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34413305

RESUMO

SMN is a ubiquitously expressed protein and is essential for life. SMN deficiency causes the neurodegenerative disease spinal muscular atrophy (SMA), the leading genetic cause of infant mortality. SMN interacts with itself and other proteins to form a complex that functions in the assembly of ribonucleoproteins. SMN is modified by SUMO (Small Ubiquitin-like Modifier), but whether sumoylation is required for the functions of SMN that are relevant to SMA pathogenesis is not known. Here, we show that inactivation of a SUMO-interacting motif (SIM) alters SMN sub-cellular distribution, the integrity of its complex, and its function in small nuclear ribonucleoproteins biogenesis. Expression of a SIM-inactivated mutant of SMN in a mouse model of SMA slightly extends survival rate with limited and transient correction of motor deficits. Remarkably, although SIM-inactivated SMN attenuates motor neuron loss and improves neuromuscular junction synapses, it fails to prevent the loss of sensory-motor synapses. These findings suggest that sumoylation is important for proper assembly and function of the SMN complex and that loss of this post-translational modification impairs the ability of SMN to correct selective deficits in the sensory-motor circuit of SMA mice.


Assuntos
Neurônios Motores/metabolismo , Atrofia Muscular Espinal/patologia , Doenças Neurodegenerativas/patologia , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Proteínas do Complexo SMN/metabolismo , Sumoilação , Sinapses/metabolismo , Animais , Animais Geneticamente Modificados , Células Cultivadas , Modelos Animais de Doenças , Humanos , Camundongos , Neurônios Motores/patologia , Atrofia Muscular Espinal/metabolismo , Doenças Neurodegenerativas/metabolismo , Sinapses/patologia , Peixe-Zebra
7.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445111

RESUMO

Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a multisystem hereditary ataxia associated with mutations in SACS, which encodes sacsin, a protein of still only partially understood function. Although mouse models of ARSACS mimic largely the disease progression seen in humans, their use in the validation of effective therapies has not yet been proposed. Recently, the teleost Danio rerio has attracted increasing attention as a vertebrate model that allows rapid and economical screening, of candidate molecules, and thus combines the advantages of whole-organism phenotypic assays and in vitro high-throughput screening assays. Through CRISPR/Cas9-based mutagenesis, we generated and characterized a zebrafish sacs-null mutant line that replicates the main features of ARSACS. The sacs-null fish showed motor impairment, hindbrain atrophy, mitochondrial dysfunction, and reactive oxygen species accumulation. As proof of principle for using these mutant fish in high-throughput screening studies, we showed that both acetyl-DL-leucine and tauroursodeoxycholic acid improved locomotor and biochemical phenotypes in sacs-/- larvae treated with these neuroprotective agents, by mediating significant rescue of the molecular functions altered by sacsin loss. Taken together, the evidence here reported shows the zebrafish to be a valuable model organism for the identification of novel molecular mechanisms and for efficient and rapid in vivo optimization and screening of potential therapeutic compounds. These findings may pave the way for new interventions targeting the earliest phases of Purkinje cell degeneration in ARSACS.


Assuntos
Proteínas de Choque Térmico/metabolismo , Fármacos Neuroprotetores/metabolismo , Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados/metabolismo , Ataxia/metabolismo , Ataxia Cerebelar/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Espasticidade Muscular/metabolismo , Mutação/genética , Fenótipo , Células de Purkinje/metabolismo , Ataxias Espinocerebelares/congênito , Ataxias Espinocerebelares/metabolismo
8.
Molecules ; 26(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34443430

RESUMO

Parkinson's disease (PD) is a currently incurable neurodegenerative disorder characterized by the loss of dopaminergic (DAergic) neurons in the substantia nigra pars compacta and α-synuclein aggregation. Accumulated evidence indicates that the saponins, especially from ginseng, have neuroprotective effects against neurodegenerative disorders. Interestingly, saponin can also be found in marine organisms such as the sea cucumber, but little is known about its effect in neurodegenerative disease, including PD. In this study, we investigated the anti-Parkinson effects of frondoside A (FA) from Cucumaria frondosa and ginsenoside Rg3 (Rg3) from Panax notoginseng in C. elegans PD model. Both saponins were tested for toxicity and optimal concentration by food clearance assay and used to treat 6-OHDA-induced BZ555 and transgenic α-synuclein NL5901 strains in C. elegans. Treatment with FA and Rg3 significantly attenuated DAergic neurodegeneration induced by 6-OHDA in BZ555 strain, improved basal slowing rate, and prolonged lifespan in the 6-OHDA-induced wild-type strain with downregulation of the apoptosis mediators, egl-1 and ced-3, and upregulation of sod-3 and cat-2. Interestingly, only FA reduced α-synuclein aggregation, rescued lifespan in NL5901, and upregulated the protein degradation regulators, including ubh-4, hsf-1, hsp-16.1 and hsp-16.2. This study indicates that both FA and Rg3 possess beneficial effects in rescuing DAergic neurodegeneration in the 6-OHDA-induced C. elegans model through suppressing apoptosis mediators and stimulating antioxidant enzymes. In addition, FA could attenuate α-synuclein aggregation through the protein degradation process.


Assuntos
Caenorhabditis elegans/fisiologia , Ginsenosídeos/farmacologia , Glicosídeos/farmacologia , Doença de Parkinson/patologia , Triterpenos/farmacologia , Animais , Animais Geneticamente Modificados , Apoptose/efeitos dos fármacos , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Ginsenosídeos/química , Ginsenosídeos/toxicidade , Glicosídeos/química , Glicosídeos/toxicidade , Longevidade/efeitos dos fármacos , Degeneração Neural/complicações , Degeneração Neural/patologia , Oxidopamina , Doença de Parkinson/complicações , Proteólise/efeitos dos fármacos , Triterpenos/química , Triterpenos/toxicidade , alfa-Sinucleína/metabolismo
9.
FASEB J ; 35(9): e21783, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34403510

RESUMO

Melatonin is a pleiotropic molecule with a variety of biological functions, which include its immunoregulatory action in mammals. Brucellosis is a worldwide endemic zoonotic disease caused by the Brucella, which not only causes huge economic losses for the livestock industry but also impacts human health. To target this problem, in current study, two marker-free transgenic sheep overexpressing melatonin synthetic enzyme ASMT (acetylserotonin O-methyltransferase) gene were generated and these melatonin enrich transgenic sheep were challenged by Brucella infection. The results showed that the serum melatonin concentration was significantly higher in transgenic sheep than that of wild type (726.92 ± 70.6074 vs 263.10 ± 34.60 pg/mL, P < .05). Brucella challenge test showed that two thirds (4/6) of the wild-type sheep had brucellosis, while none of the transgenic sheep were infected. Whole-blood RNA-seq results showed that differential expression genes (DEGs) were significantly enriched in natural killer cell-mediated cytotoxicity, phagosome, antigen processing, and presentation signaling pathways in overexpression sheep. The DEGs of toll-like receptors (TLRs) and NOD-like receptors (NLRs) families were verified by qPCR and it showed that TLR1, TLR2, TLR7, CD14, NAIP, and CXCL8 expression levels in overexpression sheep were significantly higher and NLRP1, NLRP3, and TNF expression levels were significantly lower than those of wild type. The rectal feces were subjected to 16S rDNA amplicon sequencing, and the microbial functional analysis showed that the transgenic sheep had significantly lower abundance of microbial genes related to infectious diseases compared to the wild type, indicating overexpression animals are likely more resistant to infectious diseases than wild type. Furthermore, exogenous melatonin treatment relieved brucellosis inflammation by upregulating anti-inflammatory cytokines IL-4 and downregulating pro-inflammatory IL-2, IL-6, and IFN-γ. Our preliminary results provide an informative reference for the study of the relationship between melatonin and brucellosis.


Assuntos
Acetilserotonina O-Metiltransferasa/genética , Brucelose/genética , Brucelose/imunologia , Microbioma Gastrointestinal , Transdução de Sinais/imunologia , Acetilserotonina O-Metiltransferasa/metabolismo , Animais , Animais Geneticamente Modificados , Brucelose/prevenção & controle , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Mediadores da Inflamação/imunologia , Melatonina/uso terapêutico , Ovinos/imunologia
10.
Nutrients ; 13(7)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34371921

RESUMO

The study of different natural products can provide a wealth of bioactive compounds, and more interestingly, their combination can exert a new strategy for several neurodegenerative diseases with major public health importance, such as Alzheimer's disease (AD). Here, we investigated the synergistic neuroprotective effects of a mixed extract composed of docosahexaenoic acid, Ginkgo biloba, D-pinitol, and ursolic acid in several transgenic Caenorhabditis elegans (C. elegans) and a senescence-accelerated prone mice 8 (SAMP8) model. First, we found a significantly higher survival percentage in the C. elegans group treated with the natural product mixture compared to the single extract-treated groups. Likewise, we found a significantly increased lifespan in group of C. elegans treated with the natural product mixture compared to the other groups, suggesting synergistic effects. Remarkably, we determined a significant reduction in Aß plaque accumulation in the group of C. elegans treated with the natural product mixture compared to the other groups, confirming synergy. Finally, we demonstrated better cognitive performance in the group treated with the natural product mixture in both AD models (neuronal Aß C. elegans strain CL2355 and the SAMP8 mice model), confirming the molecular results and unraveling the synergist effects of this combination. Therefore, our results proved the potential of this new natural product mixture for AD therapeutic strategies.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Comportamento Animal/efeitos dos fármacos , Produtos Biológicos/farmacologia , Encéfalo/efeitos dos fármacos , Cognição/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/metabolismo , Animais , Animais Geneticamente Modificados , Encéfalo/metabolismo , Encéfalo/patologia , Caenorhabditis elegans/genética , Modelos Animais de Doenças , Longevidade , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Placa Amiloide
11.
Nat Commun ; 12(1): 4818, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376687

RESUMO

The enteroendocrine cell (EEC)-derived incretins play a pivotal role in regulating the secretion of glucagon and insulins in mammals. Although glucagon-like and insulin-like hormones have been found across animal phyla, incretin-like EEC-derived hormones have not yet been characterised in invertebrates. Here, we show that the midgut-derived hormone, neuropeptide F (NPF), acts as the sugar-responsive, incretin-like hormone in the fruit fly, Drosophila melanogaster. Secreted NPF is received by NPF receptor in the corpora cardiaca and in insulin-producing cells. NPF-NPFR signalling resulted in the suppression of the glucagon-like hormone production and the enhancement of the insulin-like peptide secretion, eventually promoting lipid anabolism. Similar to the loss of incretin function in mammals, loss of midgut NPF led to significant metabolic dysfunction, accompanied by lipodystrophy, hyperphagia, and hypoglycaemia. These results suggest that enteroendocrine hormones regulate sugar-dependent metabolism through glucagon-like and insulin-like hormones not only in mammals but also in insects.


Assuntos
Drosophila melanogaster/metabolismo , Células Enteroendócrinas/metabolismo , Glucagon/metabolismo , Hormônios/metabolismo , Insulina/metabolismo , Neuropeptídeos/metabolismo , Animais , Animais Geneticamente Modificados , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Feminino , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Humanos , Hipoglicemia/genética , Hipoglicemia/metabolismo , Incretinas/metabolismo , Secreção de Insulina , Metabolismo dos Lipídeos/genética , Mutação , Neuropeptídeos/genética , Receptores de Neuropeptídeos/genética , Receptores de Neuropeptídeos/metabolismo , Açúcares/metabolismo
12.
Nat Commun ; 12(1): 4912, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389721

RESUMO

Polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) hybrid systems typically use complex protein-protein interactions to facilitate direct transfer of intermediates between these multimodular megaenzymes. In the canal-associated neurons (CANs) of Caenorhabditis elegans, PKS-1 and NRPS-1 produce the nemamides, the only known hybrid polyketide-nonribosomal peptides biosynthesized by animals, through a poorly understood mechanism. Here, we use genome editing and mass spectrometry to map the roles of individual PKS-1 and NRPS-1 enzymatic domains in nemamide biosynthesis. Furthermore, we show that nemamide biosynthesis requires at least five additional enzymes expressed in the CANs that are encoded by genes distributed across the worm genome. We identify the roles of these enzymes and discover a mechanism for trafficking intermediates between a PKS and an NRPS. Specifically, the enzyme PKAL-1 activates an advanced polyketide intermediate as an adenylate and directly loads it onto a carrier protein in NRPS-1. This trafficking mechanism provides a means by which a PKS-NRPS system can expand its biosynthetic potential and is likely important for the regulation of nemamide biosynthesis.


Assuntos
Vias Biossintéticas/genética , Proteínas de Caenorhabditis elegans/genética , Peptídeo Sintases/genética , Peptídeos/metabolismo , Policetídeo Sintases/genética , Policetídeos/metabolismo , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/citologia , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Cromatografia Líquida/métodos , Enzimas/genética , Enzimas/metabolismo , Expressão Gênica , Espectrometria de Massas/métodos , Estrutura Molecular , Mutação , Neurônios/metabolismo , Peptídeo Sintases/metabolismo , Peptídeos/química , Policetídeo Sintases/metabolismo , Policetídeos/química
13.
Toxicol Lett ; 350: 71-80, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34252508

RESUMO

Sanguinarine, derived from the root of Sanguinaria canadensis, have multiple biological activities, such as antimicrobial, insecticidal, antitumor, anti-inflammatory and anti-angiogenesis effect, but little is known about its toxicity on normal embryonic development. Here, we study the developmental toxicity using zebrafish model. Notably, sanguinarine caused a significant increase of the malformation rate and decrease of hatching rates and body length of zebrafish embryos. Sanguinarine also impaired the normal development of heart, liver and nerve system of zebrafish embryos. Further, the ROS level and MDA concentrations were remarkably increased, while the activity of T-SOD was decreased. In addition, obvious increase of apoptosis were observed by AO staining or TUNEL assay. Further studies showed that the oxidative stress-, apoptosis-related genes were changed, while genes of nrf2 and wnt pathways were inhibited by sangunarine. To sum up, our study will be helpful to understand the adverse effect of sanguinarine on embryonic development and the underlying molecular mechanism.


Assuntos
Apoptose/efeitos dos fármacos , Benzofenantridinas/toxicidade , Isoquinolinas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , Peixe-Zebra/embriologia , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Variação Genética , Genótipo , Modelos Animais , Raízes de Plantas/química , Raízes de Plantas/toxicidade , Sanguinaria/química , Sanguinaria/toxicidade
14.
Nat Commun ; 12(1): 4173, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234137

RESUMO

The integration of circadian and metabolic signals is essential for maintaining robust circadian rhythms and ensuring efficient metabolism and energy use. Using Drosophila as an animal model, we show that cellular protein O-GlcNAcylation exhibits robust 24-hour rhythm and represents a key post-translational mechanism that regulates circadian physiology. We observe strong correlation between protein O-GlcNAcylation rhythms and clock-controlled feeding-fasting cycles, suggesting that O-GlcNAcylation rhythms are primarily driven by nutrient input. Interestingly, daily O-GlcNAcylation rhythms are severely dampened when we subject flies to time-restricted feeding at unnatural feeding time. This suggests the presence of clock-regulated buffering mechanisms that prevent excessive O-GlcNAcylation at non-optimal times of the day-night cycle. We show that this buffering mechanism is mediated by the expression and activity of GFAT, OGT, and OGA, which are regulated through integration of circadian and metabolic signals. Finally, we generate a mathematical model to describe the key factors that regulate daily O-GlcNAcylation rhythm.


Assuntos
Ritmo Circadiano/genética , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/metabolismo , Hexosaminas/biossíntese , N-Acetilglucosaminiltransferases/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Acetilglucosamina/metabolismo , Animais , Animais Geneticamente Modificados , Vias Biossintéticas/genética , Relógios Circadianos/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Comportamento Alimentar/fisiologia , Feminino , Perfilação da Expressão Gênica , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/genética , Masculino , Modelos Animais , N-Acetilglucosaminiltransferases/genética , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo
15.
Nat Commun ; 12(1): 4239, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244495

RESUMO

Stable epigenetic changes appear uncommon, suggesting that changes typically dissipate or are repaired. Changes that stably alter gene expression across generations presumably require particular conditions that are currently unknown. Here we report that a minimal combination of cis-regulatory sequences can support permanent RNA silencing of a single-copy transgene and its derivatives in C. elegans simply upon mating. Mating disrupts competing RNA-based mechanisms to initiate silencing that can last for >300 generations. This stable silencing requires components of the small RNA pathway and can silence homologous sequences in trans. While animals do not recover from mating-induced silencing, they often recover from and become resistant to trans silencing. Recovery is also observed in most cases when double-stranded RNA is used to silence the same coding sequence in different regulatory contexts that drive germline expression. Therefore, we propose that regulatory features can evolve to oppose permanent and potentially maladaptive responses to transient change.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Interferência de RNA/fisiologia , RNA de Cadeia Dupla/genética , Animais , Animais Geneticamente Modificados , Feminino , Masculino , Elementos Reguladores de Transcrição , Reprodução/genética
16.
Nat Commun ; 12(1): 4212, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244496

RESUMO

CSR-1 is an essential Argonaute protein that binds to a subclass of 22G-RNAs targeting most germline-expressed genes. Here we show that the two isoforms of CSR-1 have distinct expression patterns; CSR-1B is ubiquitously expressed throughout the germline and during all stages of development while CSR-1A expression is restricted to germ cells undergoing spermatogenesis. Furthermore, CSR-1A associates preferentially with 22G-RNAs mapping to spermatogenesis-specific genes whereas CSR-1B-bound small RNAs map predominantly to oogenesis-specific genes. Interestingly, the exon unique to CSR-1A contains multiple dimethylarginine modifications, which are necessary for the preferential binding of CSR-1A to spermatogenesis-specific 22G-RNAs. Thus, we have discovered a regulatory mechanism for C. elegans Argonaute proteins that allows for specificity of small RNA binding between similar Argonaute proteins with overlapping temporal and spatial localization.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Interferência de RNA , Espermatogênese/genética , Animais , Animais Geneticamente Modificados , Arginina/metabolismo , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Éxons/genética , Feminino , Masculino , Metilação , Oogênese/genética , Ligação Proteica/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Interferente Pequeno/metabolismo , Processos de Determinação Sexual/genética
17.
Gene ; 799: 145811, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34224829

RESUMO

Parkinson's disease (PD) is a common neurodegenerative disorder with motor symptoms linked to the loss of dopaminergic neurons in the brain. α-Synuclein is an aggregation-prone neural protein that plays a role in the pathogenesis of PD. In our previous paper, we found that saffron; the stigma of Crocus sativus Linné (Iridaceae), and its constituents (crocin and crocetin) suppressed aggregation of α-synuclein and promoted the dissociation of α-synuclein fibrils in vitro. In this study, we investigated the effect of dietary saffron and its constituent, crocetin, in vivo on a fly PD model overexpressing several mutant α-synuclein in a tissue-specific manner. Saffron and crocetin significantly suppressed the decrease of climbing ability in the Drosophila overexpressing A30P (A30P fly PD model) or G51D (G51D fly PD model) mutated α-synuclein in neurons. Saffron and crocetin extended the life span in the G51D fly PD model. Saffron suppressed the rough-eyed phenotype and the dispersion of the size histogram of the ocular long axis in the eye of A30P fly PD model. Saffron had a cytoprotective effect on a human neuronal cell line with α-synuclein fibrils. These data showed that saffron and its constituent crocetin have protective effects on the progression of PD disease in animals in vivo and suggest that saffron and crocetin can be used to treat PD.


Assuntos
Carotenoides/farmacologia , Crocus/química , Atividade Motora/efeitos dos fármacos , Doença de Parkinson/etiologia , Degeneração Retiniana/tratamento farmacológico , Vitamina A/análogos & derivados , Animais , Animais Geneticamente Modificados , Linhagem Celular , Modelos Animais de Doenças , Drosophila melanogaster/genética , Feminino , Humanos , Longevidade/efeitos dos fármacos , Masculino , Mutação , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson/tratamento farmacológico , Degeneração Retiniana/etiologia , Degeneração Retiniana/fisiopatologia , Vitamina A/farmacologia , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , alfa-Sinucleína/toxicidade
18.
FASEB J ; 35(8): e21828, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34325494

RESUMO

Since prenatal glucocorticoids (GC) excess increases the risk of metabolic dysfunctions in the offspring and its effect on ß-cell recovery capacity remains unknown we investigated these aspects in offspring from mice treated with dexamethasone (DEX) in the late pregnancy. Half of the pups were treated with streptozotocin (STZ) on the sixth postnatal day (PN). Functional and molecular analyses were performed in male offspring on PN25 and PN225. Prenatal DEX treatment resulted in low birth weight. At PN25, both the STZ-treated offspring developed hyperglycemia and had lower ß-cell mass, in parallel with higher α-cell mass and glucose intolerance, with no impact of prenatal DEX on such parameters. At PN225, the ß-cell mass was partially recovered in the STZ-treated mice, but they remained glucose-intolerant, irrespective of being insulin sensitive. Prenatal exposition to DEX predisposed adult offspring to sustained hyperglycemia and perturbed islet function (lower insulin and higher glucagon response to glucose) in parallel with exacerbated glucose intolerance. ß-cell-specific knockdown of the Hnf4α in mice from the DS group resulted in exacerbated glucose intolerance. We conclude that high GC exposure during the prenatal period exacerbates the metabolic dysfunctions in adult life of mice exposed to STZ early in life, resulting in a lesser ability to recover the islets' function over time. This study alerts to the importance of proper management of exogenous GCs during pregnancy and a healthy postnatal lifestyle since the combination of adverse factors during the prenatal and postnatal period accentuates the predisposition to metabolic disorders in adult life.


Assuntos
Dexametasona/toxicidade , Glucocorticoides/toxicidade , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/fisiologia , Animais , Animais Geneticamente Modificados , Animais Recém-Nascidos , Dexametasona/administração & dosagem , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/administração & dosagem , Teste de Tolerância a Glucose , Insulina/farmacologia , Camundongos , Neoplasias Experimentais , Gravidez , Efeitos Tardios da Exposição Pré-Natal , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
19.
Arterioscler Thromb Vasc Biol ; 41(9): 2454-2468, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34261327

RESUMO

Objective: Extracellular vesicles (EVs) facilitate molecular transport across extracellular space, allowing local and systemic signaling during homeostasis and in disease. Extensive studies have described functional roles for EV populations, including during cardiovascular disease, but the in vivo characterization of endogenously produced EVs is still in its infancy. Because of their genetic tractability and live imaging amenability, zebrafish represent an ideal but under-used model to investigate endogenous EVs. We aimed to establish a transgenic zebrafish model to allow the in vivo identification, tracking, and extraction of endogenous EVs produced by different cell types. Approach and Results: Using a membrane-tethered fluorophore reporter system, we show that EVs can be fluorescently labeled in larval and adult zebrafish and demonstrate that multiple cell types including endothelial cells and cardiomyocytes actively produce EVs in vivo. Cell-type specific EVs can be tracked by high spatiotemporal resolution light-sheet live imaging and modified flow cytometry methods allow these EVs to be further evaluated. Additionally, cryo electron microscopy reveals the full morphological diversity of larval and adult EVs. Importantly, we demonstrate the utility of this model by showing that different cell types exchange EVs in the adult heart and that ischemic injury models dynamically alter EV production. Conclusions: We describe a powerful in vivo zebrafish model for the investigation of endogenous EVs in all aspects of cardiovascular biology and pathology. A cell membrane fluorophore labeling approach allows cell-type specific tracing of EV origin without bias toward the expression of individual protein markers and will allow detailed future examination of their function.


Assuntos
Sistema Cardiovascular/metabolismo , Vesículas Extracelulares/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Sistema Cardiovascular/embriologia , Separação Celular , Microscopia Crioeletrônica , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Células Endoteliais/ultraestrutura , Vesículas Extracelulares/genética , Vesículas Extracelulares/ultraestrutura , Citometria de Fluxo , Regulação da Expressão Gênica no Desenvolvimento , Larva/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/ultraestrutura , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Tempo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
20.
Nat Commun ; 12(1): 4336, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267196

RESUMO

Glutathione (GSH) is the most abundant cellular antioxidant. As reactive oxygen species (ROS) are widely believed to promote aging and age-related diseases, and antioxidants can neutralize ROS, it follows that GSH and its precursor, N-acetyl cysteine (NAC), are among the most popular dietary supplements. However, the long- term effects of GSH or NAC on healthy animals have not been thoroughly investigated. We employed C. elegans to demonstrate that chronic administration of GSH or NAC to young or aged animals perturbs global gene expression, inhibits skn-1-mediated transcription, and accelerates aging. In contrast, limiting the consumption of dietary thiols, including those naturally derived from the microbiota, extended lifespan. Pharmacological GSH restriction activates the unfolded protein response and increases proteotoxic stress resistance in worms and human cells. It is thus advantageous for healthy individuals to avoid excessive dietary antioxidants and, instead, rely on intrinsic GSH biosynthesis, which is fine-tuned to match the cellular redox status and to promote homeostatic ROS signaling.


Assuntos
Acetilcisteína/farmacologia , Envelhecimento/efeitos dos fármacos , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/fisiologia , Glutationa/farmacologia , Envelhecimento/genética , Envelhecimento/fisiologia , Animais , Animais Geneticamente Modificados , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ligação a DNA/genética , Suplementos Nutricionais , Escherichia coli , Feminino , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Masculino , Paraquat/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Compostos de Sulfidrila/metabolismo , Fatores de Transcrição/genética , Resposta a Proteínas não Dobradas/fisiologia
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