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1.
Cell ; 185(10): 1676-1693.e23, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35489334

RESUMO

Epidemiological studies reveal that marijuana increases the risk of cardiovascular disease (CVD); however, little is known about the mechanism. Δ9-tetrahydrocannabinol (Δ9-THC), the psychoactive component of marijuana, binds to cannabinoid receptor 1 (CB1/CNR1) in the vasculature and is implicated in CVD. A UK Biobank analysis found that cannabis was an risk factor for CVD. We found that marijuana smoking activated inflammatory cytokines implicated in CVD. In silico virtual screening identified genistein, a soybean isoflavone, as a putative CB1 antagonist. Human-induced pluripotent stem cell-derived endothelial cells were used to model Δ9-THC-induced inflammation and oxidative stress via NF-κB signaling. Knockdown of the CB1 receptor with siRNA, CRISPR interference, and genistein attenuated the effects of Δ9-THC. In mice, genistein blocked Δ9-THC-induced endothelial dysfunction in wire myograph, reduced atherosclerotic plaque, and had minimal penetration of the central nervous system. Genistein is a CB1 antagonist that attenuates Δ9-THC-induced atherosclerosis.


Assuntos
Cannabis , Doenças Cardiovasculares , Alucinógenos , Analgésicos , Animais , Agonistas de Receptores de Canabinoides/farmacologia , Dronabinol/farmacologia , Células Endoteliais , Genisteína/farmacologia , Genisteína/uso terapêutico , Inflamação/tratamento farmacológico , Camundongos , Receptor CB1 de Canabinoide , Receptores de Canabinoides
2.
Cell ; 176(5): 1128-1142.e18, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30686582

RESUMO

Collateral arteries are an uncommon vessel subtype that can provide alternate blood flow to preserve tissue following vascular occlusion. Some patients with heart disease develop collateral coronary arteries, and this correlates with increased survival. However, it is not known how these collaterals develop or how to stimulate them. We demonstrate that neonatal mouse hearts use a novel mechanism to build collateral arteries in response to injury. Arterial endothelial cells (ECs) migrated away from arteries along existing capillaries and reassembled into collateral arteries, which we termed "artery reassembly". Artery ECs expressed CXCR4, and following injury, capillary ECs induced its ligand, CXCL12. CXCL12 or CXCR4 deletion impaired collateral artery formation and neonatal heart regeneration. Artery reassembly was nearly absent in adults but was induced by exogenous CXCL12. Thus, understanding neonatal regenerative mechanisms can identify pathways that restore these processes in adults and identify potentially translatable therapeutic strategies for ischemic heart disease.


Assuntos
Circulação Colateral/fisiologia , Coração/crescimento & desenvolvimento , Regeneração/fisiologia , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Quimiocina CXCL12/metabolismo , Vasos Coronários/crescimento & desenvolvimento , Células Endoteliais/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica/fisiologia , Receptores CXCR4/metabolismo , Transdução de Sinais
4.
Proc Natl Acad Sci U S A ; 120(2): e2205371120, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36595695

RESUMO

Development of multicellular organisms is orchestrated by persistent cell-cell communication between neighboring partners. Direct interaction between different cell types can induce molecular signals that dictate lineage specification and cell fate decisions. Current single-cell RNA-seq technology cannot adequately analyze cell-cell contact-dependent gene expression, mainly due to the loss of spatial information. To overcome this obstacle and resolve cell-cell contact-specific gene expression during embryogenesis, we performed RNA sequencing of physically interacting cells (PIC-seq) and assessed them alongside similar single-cell transcriptomes derived from developing mouse embryos between embryonic day (E) 7.5 and E9.5. Analysis of the PIC-seq data identified gene expression signatures that were dependent on the presence of specific neighboring cell types. Our computational predictions, validated experimentally, demonstrated that neural progenitor (NP) cells upregulate Lhx5 and Nkx2-1 genes, when exclusively interacting with definitive endoderm (DE) cells. Moreover, there was a reciprocal impact on the transcriptome of DE cells, as they tend to upregulate Rax and Gsc when in contact with NP cells. Using individual cell transcriptome data, we formulated a means of computationally predicting the impact of one cell type on the transcriptome of its neighboring cell types. We have further developed a distinctive spatial-t-distributed stochastic neighboring embedding to display the pseudospatial distribution of cells in a 2-dimensional space. In summary, we describe an innovative approach to study contact-specific gene regulation during embryogenesis.


Assuntos
Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Animais , Camundongos , Desenvolvimento Embrionário/genética , Diferenciação Celular/genética , Transcriptoma , Análise de Sequência de RNA , Análise de Célula Única/métodos , Perfilação da Expressão Gênica
5.
Nature ; 559(7714): 356-362, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29973725

RESUMO

Arteries and veins are specified by antagonistic transcriptional programs. However, during development and regeneration, new arteries can arise from pre-existing veins through a poorly understood process of cell fate conversion. Here, using single-cell RNA sequencing and mouse genetics, we show that vein cells of the developing heart undergo an early cell fate switch to create a pre-artery population that subsequently builds coronary arteries. Vein cells underwent a gradual and simultaneous switch from venous to arterial fate before a subset of cells crossed a transcriptional threshold into the pre-artery state. Before the onset of coronary blood flow, pre-artery cells appeared in the immature vessel plexus, expressed mature artery markers, and decreased cell cycling. The vein-specifying transcription factor COUP-TF2 (also known as NR2F2) prevented plexus cells from overcoming the pre-artery threshold by inducing cell cycle genes. Thus, vein-derived coronary arteries are built by pre-artery cells that can differentiate independently of blood flow upon the release of inhibition mediated by COUP-TF2 and cell cycle factors.


Assuntos
Artérias/citologia , Vasos Coronários/citologia , Análise de Célula Única , Células-Tronco/citologia , Células-Tronco/metabolismo , Veias/citologia , Animais , Artérias/metabolismo , Fator II de Transcrição COUP/metabolismo , Ciclo Celular/genética , Diferenciação Celular , Linhagem da Célula , Vasos Coronários/metabolismo , Feminino , Masculino , Camundongos , Análise de Sequência de RNA , Veias/metabolismo
6.
Eur Heart J ; 42(41): 4264-4276, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34279605

RESUMO

AIMS: Non-compaction cardiomyopathy is a devastating genetic disease caused by insufficient consolidation of ventricular wall muscle that can result in inadequate cardiac performance. Despite being the third most common cardiomyopathy, the mechanisms underlying the disease, including the cell types involved, are poorly understood. We have previously shown that endothelial cell-specific deletion of the chromatin remodeller gene Ino80 results in defective coronary vessel development that leads to ventricular non-compaction in embryonic mouse hearts. We aimed to identify candidate angiocrines expressed by endocardial and endothelial cells (ECs) in wildtype and LVNC conditions in Tie2Cre;Ino80fl/fltransgenic embryonic mouse hearts, and test the effect of these candidates on cardiomyocyte proliferation and maturation. METHODS AND RESULTS: We used single-cell RNA-sequencing to characterize endothelial and endocardial defects in Ino80-deficient hearts. We observed a pathological endocardial cell population in the non-compacted hearts and identified multiple dysregulated angiocrine factors that dramatically affected cardiomyocyte behaviour. We identified Col15a1 as a coronary vessel-secreted angiocrine factor, downregulated by Ino80-deficiency, that functioned to promote cardiomyocyte proliferation. Furthermore, mutant endocardial and endothelial cells up-regulated expression of secreted factors, such as Tgfbi, Igfbp3, Isg15, and Adm, which decreased cardiomyocyte proliferation and increased maturation. CONCLUSIONS: These findings support a model where coronary endothelial cells normally promote myocardial compaction through secreted factors, but that endocardial and endothelial cells can secrete factors that contribute to non-compaction under pathological conditions.


Assuntos
Células Endoteliais , Miócitos Cardíacos , Animais , Endocárdio , Ventrículos do Coração , Camundongos , Miocárdio
7.
Circulation ; 142(19): 1848-1862, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-32929989

RESUMO

BACKGROUND: Endothelial cells (ECs) display considerable functional heterogeneity depending on the vessel and tissue in which they are located. Whereas these functional differences are presumably imprinted in the transcriptome, the pathways and networks that sustain EC heterogeneity have not been fully delineated. METHODS: To investigate the transcriptomic basis of EC specificity, we analyzed single-cell RNA sequencing data from tissue-specific mouse ECs generated by the Tabula Muris consortium. We used a number of bioinformatics tools to uncover markers and sources of EC heterogeneity from single-cell RNA sequencing data. RESULTS: We found a strong correlation between tissue-specific EC transcriptomic measurements generated by either single-cell RNA sequencing or bulk RNA sequencing, thus validating the approach. Using a graph-based clustering algorithm, we found that certain tissue-specific ECs cluster strongly by tissue (eg, liver, brain), whereas others (ie, adipose, heart) have considerable transcriptomic overlap with ECs from other tissues. We identified novel markers of tissue-specific ECs and signaling pathways that may be involved in maintaining their identity. Sex was a considerable source of heterogeneity in the endothelial transcriptome and we discovered Lars2 to be a gene that is highly enriched in ECs from male mice. We found that markers of heart and lung ECs in mice were conserved in human fetal heart and lung ECs. We identified potential angiocrine interactions between tissue-specific ECs and other cell types by analyzing ligand and receptor expression patterns. CONCLUSIONS: We used single-cell RNA sequencing data generated by the Tabula Muris consortium to uncover transcriptional networks that maintain tissue-specific EC identity and to identify novel angiocrine and functional relationships between tissue-specific ECs.


Assuntos
Bases de Dados de Ácidos Nucleicos , Células Endoteliais/metabolismo , RNA-Seq , Caracteres Sexuais , Análise de Célula Única , Transcriptoma , Animais , Feminino , Masculino , Camundongos , Especificidade de Órgãos
8.
Development ; 145(19)2018 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-30232173

RESUMO

The definitive endoderm (DE) is the embryonic germ layer that forms the gut tube and associated organs, including thymus, lungs, liver and pancreas. To understand how individual DE cells furnish gut organs, genetic fate mapping was performed using the Rosa26lacZ Cre-reporter paired with a tamoxifen-inducible DE-specific Cre-expressing transgene. We established a low tamoxifen dose that infrequently induced heritable lacZ expression in a single cell of individual E8.5 mouse embryos and identified clonal cell descendants at E16.5. As expected, only a fraction of the E16.5 embryos contained lacZ-positive clonal descendants and a subset of these contained descendants in multiple organs, revealing novel ontogeny. Furthermore, immunohistochemical analysis was used to identify lacZ-positive hepatocytes and biliary epithelial cells, which are the cholangiocyte precursors, in each clonally populated liver. Together, these data not only uncover novel and suspected lineage relationships between DE-derived organs, but also illustrate the bipotential nature of individual hepatoblasts by demonstrating that single hepatoblasts contribute to both the hepatocyte and the cholangiocyte lineage in vivo.


Assuntos
Mapeamento Cromossômico , Endoderma/citologia , Hepatócitos/citologia , Especificidade de Órgãos/genética , Análise de Célula Única , Células-Tronco/citologia , Animais , Ductos Biliares/citologia , Linhagem da Célula , Células Clonais , Embrião de Mamíferos/citologia , Células Epiteliais/citologia , Feminino , Hepatócitos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Células-Tronco/metabolismo
9.
Basic Res Cardiol ; 116(1): 19, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33742276

RESUMO

Endogenous capability of the post-mitotic human heart holds great promise to restore the injured myocardium. Recent evidence indicates that the extracellular vesicles (EVs) regulate cardiac homeostasis and regeneration. Here, we investigated the molecular mechanism of EVs for self-repair. We isolated EVs from human iPSC-derived cardiomyocytes (iCMs), which were exposed to hypoxic (hEVs) and normoxic conditions (nEVs), and examined their roles in in vitro and in vivo models of cardiac injury. hEV treatment significantly improved the viability of hypoxic iCMs in vitro and cardiac function of severely injured murine myocardium in vivo. Microarray analysis of the EVs revealed significantly enriched expression of the miR-106a-363 cluster (miR cluster) in hEVs vs. nEVs. This miR cluster preserved survival and contractility of hypoxia-injured iCMs and maintained murine left-ventricular (LV) chamber size, improved LV ejection fraction, and reduced myocardial fibrosis of the injured myocardium. RNA-Seq analysis identified Jag1-Notch3-Hes1 as a target intracellular pathway of the miR cluster. Moreover, the study found that the cell cycle activator and cytokinesis genes were significantly up-regulated in the iCMs treated with miR cluster and Notch3 siRNA. Together, these results suggested that the miR cluster in the EVs stimulated cardiomyocyte cell cycle re-entry by repressing Notch3 to induce cell proliferation and augment myocardial self-repair. The miR cluster may represent an effective therapeutic approach for ischemic cardiomyopathy.


Assuntos
Proliferação de Células , Vesículas Extracelulares/transplante , Células-Tronco Pluripotentes Induzidas/transplante , MicroRNAs/metabolismo , Infarto do Miocárdio/cirurgia , Miócitos Cardíacos/metabolismo , Receptor Notch3/metabolismo , Regeneração , Animais , Hipóxia Celular , Linhagem Celular , Modelos Animais de Doenças , Vesículas Extracelulares/metabolismo , Feminino , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos SCID , MicroRNAs/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/patologia , Receptor Notch3/genética , Recuperação de Função Fisiológica , Transdução de Sinais , Função Ventricular Esquerda
10.
Development ; 144(18): 3241-3252, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28760815

RESUMO

How mechanotransduction intersects with chemical and transcriptional factors to shape organogenesis is an important question in developmental biology. This is particularly relevant to the cardiovascular system, which uses mechanical signals from flowing blood to stimulate cytoskeletal and transcriptional responses that form a highly efficient vascular network. Using this system, artery size and structure are tightly regulated, but the underlying mechanisms are poorly understood. Here, we demonstrate that deletion of Smad4 increased the diameter of coronary arteries during mouse embryonic development, a phenotype that followed the initiation of blood flow. At the same time, the BMP signal transducers SMAD1/5/8 were activated in developing coronary arteries. In a culture model of blood flow-induced shear stress, human coronary artery endothelial cells failed to align when either BMPs were inhibited or SMAD4 was depleted. In contrast to control cells, SMAD4-deficient cells did not migrate against the direction of shear stress and increased proliferation rates specifically under flow. Similar alterations were seen in coronary arteries in vivo Thus, endothelial cells perceive the direction of blood flow and respond through SMAD signaling to regulate artery size.


Assuntos
Vasos Coronários/anatomia & histologia , Vasos Coronários/citologia , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Mecanotransdução Celular , Transdução de Sinais , Proteínas Smad/metabolismo , Animais , Proteínas Morfogenéticas Ósseas/metabolismo , Movimento Celular , Polaridade Celular , Proliferação de Células , Tamanho Celular , Circulação Coronária , Dilatação Patológica , Feminino , Humanos , Masculino , Camundongos Endogâmicos C57BL , Tamanho do Órgão , Fosforilação , RNA Interferente Pequeno/metabolismo , Estresse Mecânico
11.
Circ Res ; 123(4): 443-450, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-29986945

RESUMO

RATIONALE: Human-induced pluripotent stem cell-derived endothelial cells (iPSC-ECs) have risen as a useful tool in cardiovascular research, offering a wide gamut of translational and clinical applications. However, inefficiency of the currently available iPSC-EC differentiation protocol and underlying heterogeneity of derived iPSC-ECs remain as major limitations of iPSC-EC technology. OBJECTIVE: Here, we performed droplet-based single-cell RNA sequencing (scRNA-seq) of the human iPSCs after iPSC-EC differentiation. Droplet-based scRNA-seq enables analysis of thousands of cells in parallel, allowing comprehensive analysis of transcriptional heterogeneity. METHODS AND RESULTS: Bona fide iPSC-EC cluster was identified by scRNA-seq, which expressed high levels of endothelial-specific genes. iPSC-ECs, sorted by CD144 antibody-conjugated magnetic sorting, exhibited standard endothelial morphology and function including tube formation, response to inflammatory signals, and production of NO. Nonendothelial cell populations resulting from the differentiation protocol were identified, which included immature cardiomyocytes, hepatic-like cells, and vascular smooth muscle cells. Furthermore, scRNA-seq analysis of purified iPSC-ECs revealed transcriptional heterogeneity with 4 major subpopulations, marked by robust enrichment of CLDN5, APLNR, GJA5, and ESM1 genes, respectively. CONCLUSIONS: Massively parallel, droplet-based scRNA-seq allowed meticulous analysis of thousands of human iPSCs subjected to iPSC-EC differentiation. Results showed inefficiency of the differentiation technique, which can be improved with further studies based on identification of molecular signatures that inhibit expansion of nonendothelial cell types. Subtypes of bona fide human iPSC-ECs were also identified, allowing us to sort for iPSC-ECs with specific biological function and identity.


Assuntos
Células Endoteliais/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Transcriptoma , Receptores de Apelina/genética , Receptores de Apelina/metabolismo , Diferenciação Celular , Células Cultivadas , Claudina-5/genética , Claudina-5/metabolismo , Conexinas/genética , Conexinas/metabolismo , Células Endoteliais/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteoglicanas/genética , Proteoglicanas/metabolismo , Análise de Célula Única , Proteína alfa-5 de Junções Comunicantes
12.
Int J Mol Sci ; 21(21)2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33105908

RESUMO

There has been considerable interest in the clinical use of exosomes as delivery vehicles for treatments as well as for promising diagnostic biomarkers, but the physiological distribution of exosomes must be further elucidated to validate their efficacy and safety. Here, we aimed to develop novel methods to monitor exosome biodistribution in vivo using positron emission tomography (PET) and optical imaging. Exosomes were isolated from cultured mouse breast cancer cells and labeled for PET and optical imaging. In mice, radiolabeled and fluorescently labeled exosomes were injected both via lymphatic and hematogenous metastatic routes. PET and fluorescence images were obtained and quantified. Radioactivity and fluorescence intensity of ex vivo organs were measured. PET signals from exosomes in the lymphatic metastatic route were observed in the draining sentinel lymph nodes. Immunohistochemistry revealed greater exosome uptake in brachial and axillary versus inguinal lymph nodes. Following administration through the hematogenous metastasis pathway, accumulation of exosomes was clearly observed in the lungs, liver, and spleen. Exosomes from tumor cells were successfully labeled with 64Cu (or 68Ga) and fluorescence and were visualized via PET and optical imaging, suggesting that this simultaneous and rapid labeling method could provide valuable information for further exosome translational research and clinical applications.


Assuntos
Exossomos , Corantes Fluorescentes/farmacocinética , Imagem Multimodal/métodos , Animais , Carbocianinas/química , Carbocianinas/farmacocinética , Radioisótopos de Cobre , Vias de Administração de Medicamentos , Exossomos/química , Feminino , Corantes Fluorescentes/administração & dosagem , Corantes Fluorescentes/química , Radioisótopos de Gálio , Compostos Heterocíclicos com 1 Anel/química , Injeções Intravenosas , Marcação por Isótopo/métodos , Camundongos Endogâmicos BALB C , Tomografia por Emissão de Pósitrons/métodos , Distribuição Tecidual
13.
J Neurosci ; 38(50): 10672-10691, 2018 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-30381406

RESUMO

The immunopathological states of the brain induced by bacterial lipoproteins have been well characterized by using biochemical and histological assays. However, these studies have limitations in determining functional states of damaged brains involving aberrant synaptic activity and network, which makes it difficult to diagnose brain disorders during bacterial infection. To address this, we investigated the effect of Pam3CSK4 (PAM), a synthetic bacterial lipopeptide, on synaptic dysfunction of female mice brains and cultured neurons in parallel. Our functional brain imaging using PET with [18F]fluorodeoxyglucose and [18F] flumazenil revealed that the brain dysfunction induced by PAM is closely aligned to disruption of neurotransmitter-related neuronal activity and functional correlation in the region of the limbic system rather than to decrease of metabolic activity of neurons in the injection area. This finding was verified by in vivo tissue experiments that analyzed synaptic and dendritic alterations in the regions where PET imaging showed abnormal neuronal activity and network. Recording of synaptic activity also revealed that PAM reorganized synaptic distribution and decreased synaptic plasticity in hippocampus. Further study using in vitro neuron cultures demonstrated that PAM decreased the number of presynapses and the frequency of miniature EPSCs, which suggests PAM disrupts neuronal function by damaging presynapses exclusively. We also showed that PAM caused aggregation of synapses around dendrites, which may have caused no significant change in expression level of synaptic proteins, whereas synaptic number and function were impaired by PAM. Our findings could provide a useful guide for diagnosis and treatment of brain disorders specific to bacterial infection.SIGNIFICANCE STATEMENT It is challenging to diagnose brain disorders caused by bacterial infection because neural damage induced by bacterial products involves nonspecific neurological symptoms, which is rarely detected by laboratory tests with low spatiotemporal resolution. To better understand brain pathology, it is essential to detect functional abnormalities of brain over time. To this end, we investigated characteristic patterns of altered neuronal integrity and functional correlation between various regions in mice brains injected with bacterial lipopeptides using PET with a goal to apply new findings to diagnosis of brain disorder specific to bacterial infection. In addition, we analyzed altered synaptic density and function using both in vivo and in vitro experimental models to understand how bacterial lipopeptides impair brain function and network.


Assuntos
Encéfalo/diagnóstico por imagem , Lipopeptídeos/toxicidade , Rede Nervosa/diagnóstico por imagem , Neurônios/patologia , Animais , Encéfalo/efeitos dos fármacos , Células Cultivadas , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Rede Nervosa/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Tomografia por Emissão de Pósitrons/métodos , Ratos , Ratos Sprague-Dawley , Roedores
14.
Fungal Genet Biol ; 115: 64-77, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29331685

RESUMO

Sclerotinia homoeocarpa is the causal organism of dollar spot in turfgrasses and is a multinucleate fungus with a history of resistance to multiple fungicide classes. Heterokaryosis gives rise to the coexistence of genetically distinct nuclei within a cell, which contributes to genotypic and phenotypic plasticity in multinucleate fungi. We demonstrate that field isolates, resistant to either a demethylation inhibitor or methyl benzimidazole carbamate fungicide, can form heterokaryons with resistance to each fungicide and adaptability to serial combinations of different fungicide concentrations. Field isolates and putative heterokaryons were assayed on fungicide-amended media for in vitro sensitivity. Shifts in fungicide sensitivity and microsatellite genotypes indicated that heterokaryons could adapt to changes in fungicide pressure. Presence of both nuclei in heterokaryons was confirmed by detection of a single nucleotide polymorphism in the ß-tubulin gene, the presence of microsatellite alleles of both field isolates, and the live-cell imaging of two different fluorescently tagged nuclei using laser scanning confocal microscopy. Nucleic adaptability of heterokaryons to fungicides was strongly supported by the visualization of changes in fluorescently labeled nuclei to fungicide pressure. Results from this study suggest that heterokaryosis is a mechanism by which the pathogen adapts to multiple fungicide pressures in the field.


Assuntos
Ascomicetos/genética , Núcleo Celular/genética , Fungicidas Industriais/farmacologia , Doenças das Plantas/genética , Ascomicetos/efeitos dos fármacos , Ascomicetos/patogenicidade , Carbamatos/farmacologia , Núcleo Celular/efeitos dos fármacos , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Genótipo , Repetições de Microssatélites/genética , Triazóis/farmacologia
15.
Dev Dyn ; 245(3): 379-87, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26384464

RESUMO

BACKGROUND: Mesp1 is critical for early cardiomyocyte differentiation and heart development. We previously observed down-regulation of Mesp1 expression in YY1-ablated mouse embryonic hearts. However, how Mesp1 expression is mediated by YY1 is not well understood. RESULTS: We excised YY1 in the murine embryos using Sox2-cre and found that Mesp1 was down-regulated in the embryonic day (E) 7.5 mutant embryos. Also, YY1 activated the 6 kb Mesp1 regulatory element fused to a luciferase reporter. We identified two putative YY1 binding sites in the proximal promoter region of Mesp1 gene, and found that mutation of these sites significantly reduced YY1-induced activation of the Mesp1 promoter. We also uncovered one cognitive site for SP1, one of the earliest binding partners of YY1 identified. Mutation of this SP1 site repressed SP1-induced activation of the Mesp1 promoter. Moreover, YY1 and SP1 synergistically activated the Mesp1 promoter. Consistently, while Lacz expression driven by the wild-type 6 kb regulatory element of Mesp1 gene was robust in E7.5 mouse embryos, the mutation of these binding sites in the context of this 6 kb sequence substantially reduced the LacZ expression during embryogenesis. CONCLUSIONS: YY1 and SP1 independently and cooperatively govern the Mesp1 expression during embryogenesis.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Embrião de Mamíferos/embriologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Coração/embriologia , Organogênese/fisiologia , Elementos de Resposta/fisiologia , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição YY1/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Camundongos , Fator de Transcrição Sp1/genética , Fator de Transcrição YY1/genética
16.
Dev Dyn ; 244(3): 431-43, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25302779

RESUMO

BACKGROUND: The definitive endoderm arises as a naive epithelial sheet that produces the entire gut tube and associated organs including the liver, pancreas and lungs. Murine explant studies demonstrate that fibroblast growth factor (FGF) signaling from adjacent tissues is required to induce hepatic gene expression from isolated foregut endoderm. The requirement of FGF signaling during liver development is examined by means of small molecule inhibition during whole embryo culture. RESULTS: Loss of FGF signaling before hepatic induction results in morphological defects and gene expression changes that are confined to the anterior liver bud. In contrast the posterior portion of the liver bud remains relatively unaffected. Because FGF is thought to act as a morphogen during endoderm organogenesis, the ventral pancreas was also examined after FGF inhibition. Although the size of the ventral pancreas is not affected, loss of FGF signaling results in a significantly higher density of ventral pancreas cells. CONCLUSIONS: The requirement for FGF-mediated induction of hepatic gene expression differs across the anterior/posterior axis of the developing liver bud. These results underscore the importance of studying tissue differentiation in the context of the whole embryo.


Assuntos
Endoderma/embriologia , Fatores de Crescimento de Fibroblastos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Fígado/embriologia , Organogênese/fisiologia , Transdução de Sinais/fisiologia , Animais , Endoderma/citologia , Fígado/citologia , Camundongos , Especificidade de Órgãos/fisiologia
17.
Int J Stem Cells ; 16(4): 363-375, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37643761

RESUMO

Stem cells are the foundational cells for every organ and tissue in our body. Cell-based therapeutics using stem cells in regenerative medicine have received attracting attention as a possible treatment for various diseases caused by congenital defects. Stem cells such as induced pluripotent stem cells (iPSCs) as well as embryonic stem cells (ESCs), mesenchymal stem cells (MSCs), and neuroprogenitors stem cells (NSCs) have recently been studied in various ways as a cell-based therapeutic agent. When various stem cells are transplanted into a living body, they can differentiate and perform complex functions. For stem cell transplantation, it is essential to determine the suitability of the stem cell-based treatment by evaluating the origin of stem, the route of administration, in vivo bio-distribution, transplanted cell survival, function, and mobility. Currently, these various stem cells are being imaged in vivo through various molecular imaging methods. Various imaging modalities such as optical imaging, magnetic resonance imaging (MRI), ultrasound (US), positron emission tomography (PET), and single-photon emission computed tomography (SPECT) have been introduced for the application of various stem cell imaging. In this review, we discuss the principles and recent advances of in vivo molecular imaging for application of stem cell research.

18.
BMB Rep ; 55(6): 267-274, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35651326

RESUMO

Molecular imaging is used to improve the disease diagnosis, prognosis, monitoring of treatment in living subjects. Numerous molecular targets have been developed for various cellular and molecular processes in genetic, metabolic, proteomic, and cellular biologic level. Molecular imaging modalities such as Optical Imaging, Magnetic Resonance Imaging (MRI), Positron Emission Tomography (PET), Single Photon Emission Computed Tomography (SPECT), and Computed Tomography (CT) can be used to visualize anatomic, genetic, biochemical, and physiologic changes in vivo. For in vivo cell imaging, certain cells such as cancer cells, immune cells, stem cells could be labeled by direct and indirect labeling methods to monitor cell migration, cell activity, and cell effects in cell-based therapy. In case of cancer, it could be used to investigate biological processes such as cancer metastasis and to analyze the drug treatment process. In addition, transplanted stem cells and immune cells in cell-based therapy could be visualized and tracked to confirm the fate, activity, and function of cells. In conventional molecular imaging, cells can be monitored in vivo in bulk non-invasively with optical imaging, MRI, PET, and SPECT imaging. However, single cell imaging in vivo has been a great challenge due to an extremely high sensitive detection of single cell. Recently, there has been great attention for in vivo single cell imaging due to the development of single cell study. In vivo single imaging could analyze the survival or death, movement direction, and characteristics of a single cell in live subjects. In this article, we reviewed basic principle of in vivo molecular imaging and introduced recent studies for in vivo single cell imaging based on the concept of in vivo molecular imaging. [BMB Reports 2022; 55(6): 267-274].


Assuntos
Neoplasias , Proteômica , Humanos , Imageamento por Ressonância Magnética , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X
19.
BMB Rep ; 55(9): 429-438, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35725012

RESUMO

Cervical cancer is the fourth most common malignancy in women worldwide. Although infection from human papillomavirus (HPV) has been the leading cause of cervical cancer, HPV-negative cervical cancer accounts for approximately 3-8% of all cases. Previous research studies on cervical cancer have focused on HPV-positive cervical cancer due to its prevalence, resulting in HPV-negative cervical cancer receiving considerably less attention. As a result, HPV-negative cervical cancer is poorly understood. Its etiology remains elusive mainly due to limitations in research methodology such as lack of defined markers and model systems. Moreover, false HPV negativity can arise from inaccurate diagnostic methods, which also hinders the progress of research on HPV-negative cervical cancer. Since HPV-negative cervical cancer is associated with worse clinical features, greater attention is required to understand HPV-negative carcinoma. In this review, we provide a summary of knowledge gaps and current limitations of HPV-negative cervical cancer research based on current clinical statistics. We also discuss future directions for understanding the pathogenesis of HPV-independent cervical cancer. [BMB Reports 2022; 55(9): 429-438].


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Colo do Útero/patologia , Feminino , Humanos , Papillomaviridae , Infecções por Papillomavirus/complicações , Prevalência , Neoplasias do Colo do Útero/patologia
20.
Nat Commun ; 13(1): 7448, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36460642

RESUMO

Immunoglobulin family and carbohydrate vascular addressins encoded by Madcam1 and St6gal1 control lymphocyte homing into intestinal tissues, regulating immunity and inflammation. The addressins are developmentally programmed to decorate endothelial cells lining gut post-capillary and high endothelial venules (HEV), providing a prototypical example of organ- and segment-specific endothelial specialization. We identify conserved NKX-COUP-TFII composite elements (NCCE) in regulatory regions of Madcam1 and St6gal1 that bind intestinal homeodomain protein NKX2-3 cooperatively with venous nuclear receptor COUP-TFII to activate transcription. The Madcam1 element also integrates repressive signals from arterial/capillary Notch effectors. Pan-endothelial COUP-TFII overexpression induces ectopic addressin expression in NKX2-3+ capillaries, while NKX2-3 deficiency abrogates expression by HEV. Phylogenetically conserved NCCE are enriched in genes involved in neuron migration and morphogenesis of the heart, kidney, pancreas and other organs. Our results define an NKX-COUP-TFII morphogenetic code that targets expression of mucosal vascular addressins.


Assuntos
Células Endoteliais , Veias , Morfogênese/genética , Artérias , Movimento Celular
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