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1.
GM Crops Food ; 12(1): 18-24, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32787504

RESUMO

Since 1996 till 2018, the global area cultivated with GM crops has increased 113-fold, making biotech crops one of the fastest adopted crop technology in the past decades. In the European Union, only two countries still cultivate one available transgenic crop event on minor hectarage. Moreover, the number of notifications for confined field trials has dramatically dropped in the last decade. All these are happening while the EU legislation on GM crops has come under severe criticism. The percentage of EU citizens concerned about the presence of GMOs in the environment has decreased from 30% (in 2002) to 19% (in 2011), while the level of concern about the use of GM ingredients in food or drinks has decreased from 63% (in 2005) to 27% (in 2019). The steadily increasing acceptance of the EU citizens of GMOs in the environment and food, as it was recorded by Eurobarometers, should additionally ease the way and support a positive change of the legal framework that regulates the GM crops' testing and commercial cultivation in the EU.


Assuntos
Biotecnologia , Produtos Agrícolas/genética , Animais , Animais Geneticamente Modificados , União Europeia , Plantas Geneticamente Modificadas
2.
PLoS Negl Trop Dis ; 14(8): e0008627, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866158

RESUMO

The application of reverse genetics in the human filarial parasites has lagged due to the difficult biology of these organisms. Recently, we developed a co-culture system that permitted the infective larval stage of Brugia malayi to be transfected and efficiently develop to fecund adults. This was exploited to develop a piggyBac transposon-based toolkit that can be used to produce parasites with transgene sequences stably integrated into the parasite genome. However, the piggyBac system has generally been supplanted by Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) based technology, which allows precise editing of a genome. Here we report adapting the piggyBac mediated transfection system of B. malayi for CRISPR mediated knock-in insertion into the parasite genome. Suitable CRISPR insertion sites were identified in intergenic regions of the B. malayi genome. A dual reporter piggybac vector was modified, replacing the piggyBac inverted terminal repeat regions with sequences flanking the insertion site. B. malayi molting L3 were transfected with a synthetic guide RNA, the modified plasmid and the CAS9 nuclease. The transfected parasites were implanted into gerbils and allowed to develop into adults. Progeny microfilariae were recovered and screened for expression of a secreted luciferase reporter encoded in the plasmid. Approximately 3% of the microfilariae were found to secrete luciferase; all contained the transgenic sequences inserted at the expected location in the parasite genome. Using an adaptor mediated PCR assay, transgenic microfilariae were examined for the presence of off target insertions; no off-target insertions were found. These data demonstrate that CRISPR can be used to modify the genome of B. malayi, opening the way to precisely edit the genome of this important human filarial parasite.


Assuntos
Brugia Malayi/genética , Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Transfecção/métodos , Animais , Animais Geneticamente Modificados , Sequência de Bases , DNA de Helmintos/genética , Feminino , Edição de Genes , Genoma , Larva/genética , Luciferases , Microfilárias/genética
3.
Nat Commun ; 11(1): 4483, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32900993

RESUMO

The Drosophila lymph gland, the larval hematopoietic organ comprised of prohemocytes and mature hemocytes, has been a valuable model for understanding mechanisms underlying hematopoiesis and immunity. Three types of mature hemocytes have been characterized in the lymph gland: plasmatocytes, lamellocytes, and crystal cells, which are analogous to vertebrate myeloid cells, yet molecular underpinnings of the lymph gland hemocytes have been less investigated. Here, we use single-cell RNA sequencing to comprehensively analyze heterogeneity of developing hemocytes in the lymph gland, and discover previously undescribed hemocyte types including adipohemocytes, stem-like prohemocytes, and intermediate prohemocytes. Additionally, we identify the developmental trajectory of hemocytes during normal development as well as the emergence of the lamellocyte lineage following active cellular immunity caused by wasp infestation. Finally, we establish similarities and differences between embryonically derived- and larval lymph gland hemocytes. Altogether, our study provides detailed insights into the hemocyte development and cellular immune responses at single-cell resolution.


Assuntos
Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Hemócitos/citologia , Hemócitos/metabolismo , Transcriptoma , Animais , Animais Geneticamente Modificados , Diferenciação Celular/genética , Linhagem da Célula/genética , Drosophila melanogaster/metabolismo , Ectoparasitoses/genética , Ectoparasitoses/metabolismo , Ectoparasitoses/patologia , Perfilação da Expressão Gênica , Hematopoese/genética , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/fisiologia , Tecido Linfoide/citologia , Tecido Linfoide/metabolismo , Tecido Linfoide/parasitologia , RNA-Seq , Análise de Célula Única , Vespas/patogenicidade
4.
Nat Commun ; 11(1): 4477, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901019

RESUMO

Individual cells detach from cohesive ensembles during development and can inappropriately separate in disease. Although much is known about how cells separate from epithelia, it remains unclear how cells disperse from clusters lacking apical-basal polarity, a hallmark of advanced epithelial cancers. Here, using live imaging of the developmental migration program of Drosophila primordial germ cells (PGCs), we show that cluster dispersal is accomplished by stabilizing and orienting migratory forces. PGCs utilize a G protein coupled receptor (GPCR), Tre1, to guide front-back migratory polarity radially from the cluster toward the endoderm. Posteriorly positioned myosin-dependent contractile forces pull on cell-cell contacts until cells release. Tre1 mutant cells migrate randomly with transient enrichment of the force machinery but fail to separate, indicating a temporal contractile force threshold for detachment. E-cadherin is retained on the cell surface during cell separation and augmenting cell-cell adhesion does not impede detachment. Notably, coordinated migration improves cluster dispersal efficiency by stabilizing cell-cell interfaces and facilitating symmetric pulling. We demonstrate that guidance of inherent migratory forces is sufficient to disperse cell clusters under physiological settings and present a paradigm for how such events could occur across development and disease.


Assuntos
Drosophila melanogaster/embriologia , Células Germinativas Embrionárias/fisiologia , Animais , Animais Geneticamente Modificados , Fenômenos Biomecânicos , Padronização Corporal/fisiologia , Caderinas/metabolismo , Adesão Celular/fisiologia , Movimento Celular/fisiologia , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/fisiologia , Células Germinativas Embrionárias/citologia , Microscopia de Fluorescência por Excitação Multifotônica , Miosina Tipo II/metabolismo , Transdução de Sinais , Análise de Célula Única , Proteínas rho de Ligação ao GTP/metabolismo
5.
Nat Commun ; 11(1): 4468, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901021

RESUMO

Speciation constrains the flow of genetic information between populations of sexually reproducing organisms. Gaining control over mechanisms of speciation would enable new strategies to manage wild populations of disease vectors, agricultural pests, and invasive species. Additionally, such control would provide safe biocontainment of transgenes and gene drives. Here, we demonstrate a general approach to create engineered genetic incompatibilities (EGIs) in the model insect Drosophila melanogaster. EGI couples a dominant lethal transgene with a recessive resistance allele. Strains homozygous for both elements are fertile and fecund when they mate with similarly engineered strains, but incompatible with wild-type strains that lack resistant alleles. EGI genotypes can also be tuned to cause hybrid lethality at different developmental life-stages. Further, we demonstrate that multiple orthogonal EGI strains of D. melanogaster can be engineered to be mutually incompatible with wild-type and with each other. EGI is a simple and robust approach in multiple sexually reproducing organisms.


Assuntos
Drosophila melanogaster/genética , Engenharia Genética/métodos , Especiação Genética , Animais , Animais Geneticamente Modificados , Cruzamentos Genéticos , Feminino , Genes de Insetos , Genes Letais , Genótipo , Hibridização Genética , Masculino , Modelos Genéticos , Transgenes
6.
Nat Commun ; 11(1): 4496, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901024

RESUMO

Aging is characterized by the loss of homeostasis and the general decline of physiological functions, accompanied by various degenerative diseases and increased rates of mortality. Aging targeting small molecule screens have been performed many times, however, few have focused on endogenous metabolic intermediates-metabolites. Here, using C. elegans lifespan assays, we conducted a worm metabolite screen and identified an eukaryotes conserved metabolite, myo-inositol (MI), to extend lifespan, increase mobility and reduce fat content. Genetic analysis of enzymes in MI metabolic pathway suggest that MI alleviates aging through its derivative PI(4,5)P2. MI and PI(4,5)P2 are precursors of PI(3,4,5)P3, which is negatively related to longevity. The longevity effect of MI is dependent on the tumor suppressor gene, daf-18 (homologous to mouse Pten), independent of its classical pathway downstream genes, akt or daf-16. Furthermore, we found MI effects on aging and lifespan act through mitophagy regulator PTEN induced kinase-1 (pink-1) and mitophagy. MI's anti-aging effect is also conserved in mouse, indicating a conserved mechanism in mammals.


Assuntos
Envelhecimento/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Inositol/metabolismo , Longevidade/fisiologia , PTEN Fosfo-Hidrolase/metabolismo , Envelhecimento/efeitos dos fármacos , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Linhagem Celular Tumoral , Feminino , Fatores de Transcrição Forkhead/genética , Inositol/administração & dosagem , Locomoção/fisiologia , Longevidade/efeitos dos fármacos , Redes e Vias Metabólicas/genética , Metabolômica , Camundongos , Mitofagia/fisiologia , Modelos Animais , Fosfatos de Fosfatidilinositol/metabolismo , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , RNA-Seq
7.
Nat Commun ; 11(1): 4491, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901033

RESUMO

The functionality of the nervous system requires transmission of information along axons with high speed and precision. Conductance velocity depends on axonal diameter whereas signaling precision requires a block of electrical crosstalk between axons, known as ephaptic coupling. Here, we use the peripheral nervous system of Drosophila larvae to determine how glia regulates axonal properties. We show that wrapping glial differentiation depends on gap junctions and FGF-signaling. Abnormal glial differentiation affects axonal diameter and conductance velocity and causes mild behavioral phenotypes that can be rescued by a sphingosine-rich diet. Ablation of wrapping glia does not further impair axonal diameter and conductance velocity but causes a prominent locomotion phenotype that cannot be rescued by sphingosine. Moreover, optogenetically evoked locomotor patterns do not depend on conductance speed but require the presence of wrapping glial processes. In conclusion, our data indicate that wrapping glia modulates both speed and precision of neuronal signaling.


Assuntos
Drosophila melanogaster/fisiologia , Animais , Animais Geneticamente Modificados , Axônios/fisiologia , Diferenciação Celular , Proteínas de Drosophila/genética , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Larva/citologia , Larva/fisiologia , Locomoção/fisiologia , Modelos Neurológicos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Neuroglia/citologia , Neuroglia/fisiologia , Optogenética , Sistema Nervoso Periférico/citologia , Sistema Nervoso Periférico/fisiologia , Fenótipo , Receptores de Fatores de Crescimento de Fibroblastos/fisiologia , Transdução de Sinais
8.
Nat Commun ; 11(1): 4516, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908137

RESUMO

Acinar metaplasia is an initial step in a series of events that can lead to pancreatic cancer. Here we perform single-cell RNA-sequencing of mouse pancreas during the progression from preinvasive stages to tumor formation. Using a reporter gene, we identify metaplastic cells that originated from acinar cells and express two transcription factors, Onecut2 and Foxq1. Further analyses of metaplastic acinar cell heterogeneity define six acinar metaplastic cell types and states, including stomach-specific cell types. Localization of metaplastic cell types and mixture of different metaplastic cell types in the same pre-malignant lesion is shown. Finally, single-cell transcriptome analyses of tumor-associated stromal, immune, endothelial and fibroblast cells identify signals that may support tumor development, as well as the recruitment and education of immune cells. Our findings are consistent with the early, premalignant formation of an immunosuppressive environment mediated by interactions between acinar metaplastic cells and other cells in the microenvironment.


Assuntos
Células Acinares/patologia , Carcinoma Ductal Pancreático/genética , Regulação Neoplásica da Expressão Gênica , Pâncreas/patologia , Neoplasias Pancreáticas/genética , Lesões Pré-Cancerosas/genética , Animais , Animais Geneticamente Modificados , Biópsia , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/cirurgia , Diferenciação Celular , Modelos Animais de Doenças , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Heterogeneidade Genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Estimativa de Kaplan-Meier , Masculino , Metaplasia/genética , Camundongos , Mutação , Pâncreas/citologia , Pâncreas/cirurgia , Pancreatectomia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Lesões Pré-Cancerosas/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , RNA-Seq , Análise de Célula Única , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Microambiente Tumoral/genética
9.
Nat Commun ; 11(1): 4505, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908148

RESUMO

Evidence for transgenerational inheritance of epigenetic information in vertebrates is scarce. Aberrant patterns of DNA methylation in gametes may set the stage for transmission into future generations. Here, we describe a viable hypomorphic allele of dnmt1 in zebrafish that causes widespread demethylation of CpG dinucleotides in sperm and somatic tissues. We find that homozygous mutants are essentially normal, with the exception of drastically impaired lymphopoiesis, affecting both larval and adult phases of T cell development. The phenotype of impaired larval (but not adult) T cell development is transmitted to subsequent generations by genotypically wildtype fish. We further find that about 200 differentially methylated regions in sperm DNA of transmitting and non-transmitting males, including hypermethylated sites associated with runx3 and rptor genes, whose reduced activities are associated with impaired larval T cell development. Our results indicate a particular sensitivity of larval T cell development to transgenerationally inherited epimutations.


Assuntos
Diferenciação Celular/genética , Genes Recessivos , Larva/crescimento & desenvolvimento , Linfopoese/genética , Linfócitos T/fisiologia , Alelos , Animais , Animais Geneticamente Modificados , Subunidade alfa 3 de Fator de Ligação ao Core/genética , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Metilação de DNA , Epigênese Genética , Feminino , Genética , Larva/citologia , Masculino , Mutação , Proteína Regulatória Associada a mTOR/genética , Espermatozoides/metabolismo , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
10.
Nat Commun ; 11(1): 4529, 2020 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-32913184

RESUMO

Although Huntington's disease (HD) is a well studied Mendelian genetic disorder, less is known about its associated epigenetic changes. Here, we characterize DNA methylation levels in six different tissues from 3 species: a mouse huntingtin (Htt) gene knock-in model, a transgenic HTT sheep model, and humans. Our epigenome-wide association study (EWAS) of human blood reveals that HD mutation status is significantly (p < 10-7) associated with 33 CpG sites, including the HTT gene (p = 6.5 × 10-26). These Htt/HTT associations were replicated in the Q175 Htt knock-in mouse model (p = 6.0 × 10-8) and in the transgenic sheep model (p = 2.4 × 10-88). We define a measure of HD motor score progression among manifest HD cases based on multiple clinical assessments. EWAS of motor progression in manifest HD cases exhibits significant (p < 10-7) associations with methylation levels at three loci: near PEX14 (p = 9.3 × 10-9), GRIK4 (p = 3.0 × 10-8), and COX4I2 (p = 6.5 × 10-8). We conclude that HD is accompanied by profound changes of DNA methylation levels in three mammalian species.


Assuntos
Metilação de DNA , Epigênese Genética , Proteína Huntingtina/genética , Doença de Huntington/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Animais Geneticamente Modificados , Comportamento Animal , Ilhas de CpG/genética , Estudos Transversais , Modelos Animais de Doenças , Progressão da Doença , Feminino , Seguimentos , Técnicas de Introdução de Genes , Loci Gênicos , Estudo de Associação Genômica Ampla , Carga Global da Doença , Humanos , Doença de Huntington/sangue , Doença de Huntington/diagnóstico , Doença de Huntington/epidemiologia , Estudos Longitudinais , Masculino , Camundongos , Pessoa de Meia-Idade , Mutação , Estudos Prospectivos , Proteínas Recombinantes/genética , Sistema de Registros/estatística & dados numéricos , Índice de Gravidade de Doença , Ovinos , Adulto Jovem
11.
Nat Commun ; 11(1): 4653, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938923

RESUMO

Cancer cells demand excess nutrients to support their proliferation, but how tumours exploit extracellular amino acids during systemic metabolic perturbations remain incompletely understood. Here, we use a Drosophila model of high-sugar diet (HSD)-enhanced tumourigenesis to uncover a systemic host-tumour metabolic circuit that supports tumour growth. We demonstrate coordinate induction of systemic muscle wasting with tumour-autonomous Yorkie-mediated SLC36-family amino acid transporter expression as a proline-scavenging programme to drive tumourigenesis. We identify Indole-3-propionic acid as an optimal amino acid derivative to rationally target the proline-dependency of tumour growth. Insights from this whole-animal Drosophila model provide a powerful approach towards the identification and therapeutic exploitation of the amino acid vulnerabilities of tumourigenesis in the context of a perturbed systemic metabolic network.


Assuntos
Açúcares da Dieta/efeitos adversos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiopatologia , Neoplasias Experimentais/fisiopatologia , Prolina/metabolismo , Sistemas de Transporte de Aminoácidos/genética , Sistemas de Transporte de Aminoácidos/metabolismo , Animais , Animais Geneticamente Modificados , Carcinogênese , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Hemolinfa/efeitos dos fármacos , Hemolinfa/metabolismo , Larva , Debilidade Muscular/induzido quimicamente , Debilidade Muscular/patologia , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/patologia , Neoplasias Experimentais/etiologia , Proteínas Nucleares/genética , Receptores Proteína Tirosina Quinases/metabolismo , Transativadores/genética , Proteínas ras/genética
12.
Nat Commun ; 11(1): 4677, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938929

RESUMO

The Integrated Stress Response (ISR) helps metazoan cells adapt to cellular stress by limiting the availability of initiator methionyl-tRNA for translation. Such limiting conditions paradoxically stimulate the translation of ATF4 mRNA through a regulatory 5' leader sequence with multiple upstream Open Reading Frames (uORFs), thereby activating stress-responsive gene expression. Here, we report the identification of two critical regulators of such ATF4 induction, the noncanonical initiation factors eIF2D and DENR. Loss of eIF2D and DENR in Drosophila results in increased vulnerability to amino acid deprivation, susceptibility to retinal degeneration caused by endoplasmic reticulum (ER) stress, and developmental defects similar to ATF4 mutants. eIF2D requires its RNA-binding motif for regulation of 5' leader-mediated ATF4 translation. Consistently, eIF2D and DENR deficient human cells show impaired ATF4 protein induction in response to ER stress. Altogether, our findings indicate that eIF2D and DENR are critical mediators of ATF4 translational induction and stress responses in vivo.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Estresse do Retículo Endoplasmático/genética , Fatores de Iniciação em Eucariotos/genética , Biossíntese de Proteínas , Fatores de Transcrição/genética , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Animais , Animais Geneticamente Modificados , Sítios de Ligação , Linhagem Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Fatores de Iniciação em Eucariotos/metabolismo , Humanos , Mutação , Fases de Leitura Aberta , Interferência de RNA , Degeneração Retiniana/genética , Fatores de Transcrição/metabolismo
13.
Elife ; 92020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32876563

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) and transmissible gastroenteritis virus (TGEV) are two highly infectious and lethal viruses causing major economic losses to pig production. Here, we report generation of double-gene-knockout (DKO) pigs harboring edited knockout alleles for known receptor proteins CD163 and pAPN and show that DKO pigs are completely resistant to genotype 2 PRRSV and TGEV. We found no differences in meat-production or reproductive-performance traits between wild-type and DKO pigs, but detected increased iron in DKO muscle. Additional infection challenge experiments showed that DKO pigs exhibited decreased susceptibility to porcine deltacoronavirus (PDCoV), thus offering unprecedented in vivo evidence of pAPN as one of PDCoV receptors. Beyond showing that multiple gene edits can be combined in a livestock animal to achieve simultaneous resistance to two major viruses, our study introduces a valuable model for investigating infection mechanisms of porcine pathogenic viruses that exploit pAPN or CD163 for entry.


Assuntos
Antígenos CD13/deficiência , Infecções por Coronavirus/prevenção & controle , Coronavirus/patogenicidade , Gastroenterite Suína Transmissível/prevenção & controle , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Receptores de Superfície Celular/deficiência , Vírus da Gastroenterite Transmissível/patogenicidade , Animais , Animais Geneticamente Modificados , Antígenos CD/genética , Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/genética , Antígenos de Diferenciação Mielomonocítica/imunologia , Composição Corporal , Antígenos CD13/genética , Antígenos CD13/imunologia , Coronavirus/imunologia , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Suscetibilidade a Doenças , Gastroenterite Suína Transmissível/genética , Gastroenterite Suína Transmissível/imunologia , Gastroenterite Suína Transmissível/virologia , Técnicas de Silenciamento de Genes , Interações entre Hospedeiro e Microrganismos , Indústria de Embalagem de Carne , Fenótipo , Síndrome Respiratória e Reprodutiva Suína/genética , Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/imunologia , Sus scrofa/genética , Suínos , Vírus da Gastroenterite Transmissível/imunologia , Ganho de Peso
14.
Arterioscler Thromb Vasc Biol ; 40(9): 2095-2107, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32757647

RESUMO

OBJECTIVE: Apo (apolipoprotein) CIII mediates the metabolism of triglyceride (TG)-rich lipoproteins. High levels of plasma apoCIII are positively correlated with the plasma TG levels and increase the cardiovascular risk. However, whether apoCIII is directly involved in the development of atherosclerosis has not been fully elucidated. Approach and Results: To examine the possible roles of apoCIII in lipoprotein metabolism and atherosclerosis, we generated apoCIII KO (knockout) rabbits using ZFN (zinc finger nuclease) technique. On a normal standard diet, apoCIII KO rabbits exhibited significantly lower plasma levels of TG than those of WT (wild type) rabbits while total cholesterol and HDL (high-density lipoprotein) cholesterol levels were unchanged. Analysis of lipoproteins isolated by sequential ultracentrifugation revealed that reduced plasma TG levels in KO rabbits were accompanied by prominent reduction of VLDLs (very-low-density lipoproteins) and IDLs (intermediate-density lipoproteins). In addition, KO rabbits showed faster TG clearance rate after intravenous fat load than WT rabbits. On a cholesterol-rich diet, KO rabbits exhibited constantly and significantly lower levels of plasma total cholesterol and TG than WT rabbits, which was caused by a remarkable reduction of ß-VLDLs-the major atherogenic lipoproteins. ß-VLDLs of KO rabbits showed higher uptake by cultured hepatocytes and were cleared faster from the circulation than ß-VLDLs isolated from WT rabbits. Both aortic and coronary atherosclerosis was significantly reduced in KO rabbits compared with WT rabbits. CONCLUSIONS: These results indicate that apoCIII deficiency facilitates TG-rich lipoprotein catabolism, and therapeutic inhibition of apoCIII expression may become a novel means not only for the treatment of hyperlipidemia but also for atherosclerosis.


Assuntos
Doenças da Aorta/prevenção & controle , Apolipoproteína C-III/deficiência , Aterosclerose/prevenção & controle , Doença da Artéria Coronariana/prevenção & controle , Triglicerídeos/sangue , Animais , Animais Geneticamente Modificados , Doenças da Aorta/genética , Doenças da Aorta/metabolismo , Doenças da Aorta/patologia , Apolipoproteína C-III/genética , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Biomarcadores/sangue , HDL-Colesterol/sangue , VLDL-Colesterol/sangue , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , Modelos Animais de Doenças , Feminino , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Lipoproteínas IDL/sangue , Fígado/metabolismo , Masculino , Oxirredução , Placa Aterosclerótica , Coelhos
15.
PLoS Genet ; 16(8): e1008963, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32780743

RESUMO

Long-term memory (LTM) formation depends on the conversed cAMP response element-binding protein (CREB)-dependent gene transcription followed by de novo protein synthesis. Thirsty fruit flies can be trained to associate an odor with water reward to form water-reward LTM (wLTM), which can last for over 24 hours without a significant decline. The role of de novo protein synthesis and CREB-regulated gene expression changes in neural circuits that contribute to wLTM remains unclear. Here, we show that acute inhibition of protein synthesis in the mushroom body (MB) αß or γ neurons during memory formation using a cold-sensitive ribosome-inactivating toxin disrupts wLTM. Furthermore, adult stage-specific expression of dCREB2b in αß or γ neurons also disrupts wLTM. The MB αß and γ neurons can be further classified into five different neuronal subsets including αß core, αß surface, αß posterior, γ main, and γ dorsal. We observed that the neurotransmission from αß surface and γ dorsal neuron subsets is required for wLTM retrieval, whereas the αß core, αß posterior, and γ main are dispensable. Adult stage-specific expression of dCREB2b in αß surface and γ dorsal neurons inhibits wLTM formation. In vivo calcium imaging revealed that αß surface and γ dorsal neurons form wLTM traces with different dynamic properties, and these memory traces are abolished by dCREB2b expression. Our results suggest that a small population of neurons within the MB circuits support long-term storage of water-reward memory in Drosophila.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Memória de Longo Prazo/fisiologia , Neurônios/metabolismo , Olfato/genética , Transativadores/genética , Animais , Animais Geneticamente Modificados , Cálcio/metabolismo , Drosophila melanogaster/fisiologia , Corpos Pedunculados/fisiologia , Neurônios/fisiologia , Biossíntese de Proteínas/genética , Recompensa , Olfato/fisiologia , Transmissão Sináptica/genética , Água
16.
Transplantation ; 104(8): 1566-1573, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32732833

RESUMO

BACKGROUND: Xenogeneic organ transplantation has been proposed as a potential approach to fundamentally solve organ shortage problem. Xenogeneic immune responses across species is one of the major obstacles for clinic application of xeno-organ transplantation. The generation of glycoprotein galactosyltransferase α 1, 3 (GGTA1) knockout pigs has greatly contributed to the reduction of hyperacute xenograft rejection. However, severe xenograft rejection can still be induced by xenoimmune responses to the porcine major histocompatibility complex antigens swine leukocyte antigen class I and class II. METHODS: We simultaneously depleted GGTA1, ß2-microglobulin (ß2M), and major histocompatibility complex class II transactivator (CIITA) genes using clustered regularly interspaced short palindromic repeats and CRISPR-associated proteins technology in Bamma pig fibroblast cells, which were further used to generate GGTA1ß2MCIITA triple knockout (GBC-3KO) pigs by nuclear transfer. RESULTS: The genotype of GBC-3KO pigs was confirmed by polymerase chain reaction and Sanger sequencing, and the loss of expression of α-1,3-galactose, SLA-I, and SLA-II was demonstrated by flow cytometric analysis using fluorescent-conjugated lectin from bandeiraea simplicifolia, anti-ß2-microglobulin, and swine leukocyte antigen class II DR antibodies. Furthermore, mixed lymphocyte reaction assay revealed that peripheral blood mononuclear cells from GBC-3KO pigs were significantly less effective than (WT) pig peripheral blood mononuclear cells in inducing human CD3CD4 and CD3CD8 T-cell activation and proliferation. In addition, GBC-3KO pig skin grafts showed a significantly prolonged survival in immunocompetent C57BL/6 mice, when compared with wild-type pig skin grafts. CONCLUSIONS: Taken together, these results demonstrate that elimination of GGTA1, ß2M, and CIITA genes in pigs can effectively alleviate xenogeneic immune responses and prolong pig organ survival in xenogenesis. We believe that this work will facilitate future research in xenotransplantation.


Assuntos
Rejeição de Enxerto/prevenção & controle , Xenoenxertos/imunologia , Transplante de Órgãos/métodos , Transplante Heterólogo/métodos , Aloenxertos/provisão & distribução , Animais , Animais Geneticamente Modificados/imunologia , Sistemas CRISPR-Cas/genética , Modelos Animais de Doenças , Feminino , Galactosiltransferases/genética , Galactosiltransferases/imunologia , Técnicas de Inativação de Genes/métodos , Genes MHC da Classe II/genética , Genes MHC da Classe II/imunologia , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/genética , Sobrevivência de Enxerto/imunologia , Xenoenxertos/transplante , Humanos , Masculino , Camundongos , Transplante de Órgãos/efeitos adversos , Suínos/genética , Suínos/imunologia , Transplante Heterólogo/efeitos adversos , Microglobulina beta-2/genética , Microglobulina beta-2/imunologia
17.
Pestic Biochem Physiol ; 169: 104674, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32828379

RESUMO

There is an on-going need to develop new insecticides that are not compromised by resistance and that have improved environmental profiles. However, the cost of developing novel compounds has increased significantly over the last two decades. This is in part due to increased regulatory requirements, including the need to screen both pest and pollinator insect species to ensure that pre-existing resistance will not hamper the efficacy of a new insecticide via cross-resistance, or adversely affect non-target insect species. To add to this problem the collection and maintenance of toxicologically relevant pest and pollinator species and strains is costly and often difficult. Here we present Fly-Tox, a panel of publicly available transgenic Drosophila melanogaster lines each containing one or more pest or pollinator P450 genes that have been previously shown to metabolise insecticides. We describe the range of ways these tools can be used, including in predictive screens to avoid pre-existing cross-resistance, to identify potential resistance-breaking inhibitors, in the initial assessment of potential insecticide toxicity to bee pollinators, and identifying harmful pesticide-pesticide interactions.


Assuntos
Resistência a Inseticidas/efeitos dos fármacos , Inseticidas/farmacologia , Animais , Animais Geneticamente Modificados , Abelhas , Sistema Enzimático do Citocromo P-450 , Drosophila melanogaster/efeitos dos fármacos
18.
PLoS Pathog ; 16(8): e1008794, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32813725

RESUMO

Wolbachia are the world's most common, maternally-inherited, arthropod endosymbionts. Their worldwide distribution is due, in part, to a selfish drive system termed cytoplasmic incompatibility (CI) that confers a relative fitness advantage to females that transmit Wolbachia to their offspring. CI results in embryonic death when infected males mate with uninfected females but not infected females. Under the Two-by-One genetic model of CI, males expressing the two phage WO proteins CifA and CifB cause CI, and females expressing CifA rescue CI. While each protein is predicted to harbor three functional domains, there is no knowledge on how sites across these Cif domains, rather than in any one particular domain, contribute to CI and rescue. Here, we use evolution-guided, substitution mutagenesis of conserved amino acids across the Cif proteins, coupled with transgenic expression in uninfected Drosophila melanogaster, to determine the functional impacts of conserved residues evolving mostly under purifying selection. We report that amino acids in CifA's N-terminal unannotated region and annotated catalase-related domain are important for both complete CI and rescue, whereas C-terminal residues in CifA's putative domain of unknown function are solely important for CI. Moreover, conserved CifB amino acids in the predicted nucleases, peptidase, and unannotated regions are essential for CI. Taken together, these findings indicate that (i) all CifA amino acids determined to be crucial in rescue are correspondingly crucial in CI, (ii) an additional set of CifA amino acids are uniquely important in CI, and (iii) CifB amino acids across the protein, rather than in one particular domain, are all crucial for CI. We discuss how these findings advance an expanded view of Cif protein evolution and function, inform the mechanistic and biochemical bases of Cif-induced CI/rescue, and continue to substantiate the Two-by-One genetic model of CI.


Assuntos
Proteínas de Bactérias/metabolismo , Evolução Biológica , Citoplasma/metabolismo , Drosophila melanogaster/microbiologia , Infecções por Bactérias Gram-Negativas/metabolismo , Mutação , Wolbachia/fisiologia , Animais , Animais Geneticamente Modificados/microbiologia , Animais Geneticamente Modificados/fisiologia , Proteínas de Bactérias/genética , Citoplasma/microbiologia , Drosophila melanogaster/fisiologia , Feminino , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/patologia , Masculino
19.
Nat Commun ; 11(1): 3920, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32764605

RESUMO

How the genome activates or silences transcriptional programmes governs organ formation. Little is known in human embryos undermining our ability to benchmark the fidelity of stem cell differentiation or cell programming, or interpret the pathogenicity of noncoding variation. Here, we study histone modifications across thirteen tissues during human organogenesis. We integrate the data with transcription to build an overview of how the human genome differentially regulates alternative organ fates including by repression. Promoters from nearly 20,000 genes partition into discrete states. Key developmental gene sets are actively repressed outside of the appropriate organ without obvious bivalency. Candidate enhancers, functional in zebrafish, allow imputation of tissue-specific and shared patterns of transcription factor binding. Overlaying more than 700 noncoding mutations from patients with developmental disorders allows correlation to unanticipated target genes. Taken together, the data provide a comprehensive genomic framework for investigating normal and abnormal human development.


Assuntos
Deficiências do Desenvolvimento/genética , Epigênese Genética , Organogênese/genética , Animais , Animais Geneticamente Modificados , Bases de Dados Genéticas , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica no Desenvolvimento , Código das Histonas/genética , Humanos , Modelos Genéticos , Mutação , Organogênese/fisiologia , Regiões Promotoras Genéticas , Distribuição Tecidual , Fatores de Transcrição/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética
20.
PLoS One ; 15(8): e0237775, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32813739

RESUMO

Nile tilapia, Oreochromis niloticus is the third most commonly farmed finfish species in the world, accounting for nearly 5% of global aquaculture production. In the past few decades much of the success of this species has been attributed to the development and distribution of Genetically Improved Farmed Tilapia (GIFT). Despite the increasing availability of GIFT, the productivity of small-scale farming remains highly variable, particularly in developing nations. Commercial fish-feed pellets can increase fish farm productivity; however, many small-scale farmers rely on other means of feeding fish due to the high cost and limited availability of commercial fish feed pellets. Therefore, understanding how locally-sourced feeds affect the production of GIFT is an important step towards improving feeding practices, particularly for farmers with low financial capital. This study used stable isotope analysis (SIA) and 16S rRNA gene sequencing to compare the effects of a locally-sourced vegetable-based diet and commercial pellet-based diets on the relative condition, nutrient assimilation patterns and gastrointestinal microbiota of GIFT. GIFT fed a locally-sourced diet were smaller, and in a significantly poorer condition than those fed with commercial fish feeds. SIA showed no differences in dietary carbon between the two diets; however, δ13C, poor fish condition and the abundance of specific bacterial taxa (of such as Fusobacteria) were correlated. SIA revealed that GIFT fed locally-sourced diets that predominantly consisted of vegetables were significantly enriched in δ15N despite a perceived lack of dietary protein. This enrichment suggests that GIFT fed a locally-sourced diet may be supplementing their diet via cannibalism, a behaviour representative of poor farming practice. Overall this study highlights the need to increase the availability of suitable GIFT feeds in developing nations. The development a low-cost feed alternative could improve the success of small-scale GIFT farmers in PNG, increasing both food and income security within the region.


Assuntos
Ração Animal , Animais Geneticamente Modificados/metabolismo , Aquicultura/métodos , Ciclídeos/metabolismo , Microbioma Gastrointestinal/fisiologia , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/microbiologia , Aquicultura/economia , Aquicultura/organização & administração , Canibalismo , Ciclídeos/genética , Ciclídeos/microbiologia , DNA Bacteriano/isolamento & purificação , Suplementos Nutricionais/economia , Eficiência Organizacional/economia , Fazendas/economia , Fazendas/organização & administração , New South Wales , Nutrientes/metabolismo , RNA Ribossômico 16S/genética
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