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1.
Tumour Biol ; 42(9): 1010428320962588, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32996421

RESUMO

A missense mutation of the guanine nucleotide binding protein alpha stimulating activity polypeptide 1 (GNAS) gene, typically Arg201Cys or Arg201His (R201H/R201C), leads to constitutive activation of the Gsα-cyclic AMP (cAMP) signaling pathway that causes several diseases. However, no germline mutations of GNAS have been identified to date, likely due to their lethality, and no robust human cell models have been generated. Therefore, the aim of this study was to generate GNAS-mutated disease-specific induced pluripotent stem cells as a model for these diseases. We then analyzed the functionality of this induced pluripotent stem cell model and differentiated epithelial cells. We generated disease-specific induced pluripotent stem cells by introducing a mutation in GNAS with the clustered regularly interspaced short palindromic repeats (CRISPR) nickase method, which has lower off-target effects than the conventional CRISPR/Cas9 method. We designed the target vector to contain the R201H mutation in GNAS, which was transfected into human control induced pluripotent stem cells (Nips-B2) by electroporation. We confirmed the establishment of GNASR201H-mutated (GNASR201H/+) induced pluripotent stem cells that exhibited a pluripotent stem cell phenotype. We analyzed the effect of the mutation on cAMP production, and further generated teratomas for immunohistochemical analysis of the luminal epithelial structure. GNAS-mutated induced pluripotent stem cells showed significantly higher levels of intracellular cAMP, which remained elevated state for a long time upon hormonal stimulation with parathyroid hormone or adrenocorticotropic hormone. Immunohistochemical analysis revealed that several mucins, including MUC1, 2, and MUC5AC, are expressed in cytokeratin 18 (CK18)-positive epithelial cells. However, we found few CK18-positive cells in mutated induced pluripotent stem cell-derived teratoma tissues, and reduced MUCINs expression in mutated epithelial cells. There was no difference in CDX2 expression; however, mutated epithelial cells were positive for CEA and CA19-9 expression. GNASR201H-mutated induced pluripotent stem cells and GNASR201H-mutated epithelial cells have distinct phenotypic and differentiation characteristics. We successfully established GNASR201H-mutated human induced pluripotent stem cells with increased cAMP production. Considering the differentiation potential of induced pluripotent stem cells, these cells will be useful as a model for elucidating the pathological mechanisms of GNAS-mutated diseases.


Assuntos
Cromograninas/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Células-Tronco Pluripotentes Induzidas/patologia , Modelos Biológicos , Mutação , Teratoma/patologia , Animais , Sistemas CRISPR-Cas , Células Cultivadas , Cromograninas/antagonistas & inibidores , Subunidades alfa Gs de Proteínas de Ligação ao GTP/antagonistas & inibidores , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Camundongos , Camundongos SCID , Teratoma/genética
2.
Yonsei Med J ; 61(9): 816-825, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32882766

RESUMO

PURPOSE: To understand the pathophysiology of Best disease (BD) and autosomal recessive bestrophinopathy (ARB) by establishing an in vitro model using human induced pluripotent stem cell (iPSC). MATERIALS AND METHODS: Human iPSC lines were generated from mononuclear cells in peripheral blood of one ARB patient, one autosomal dominant BD patient, and two normal controls. Immunocytochemistry and reverse transcriptase polymerase chain reaction in iPSC lines were conducted to demonstrate the pluripotent markers. After the differentiation of iPSC into functional retinal pigment epithelium (RPE), morphological characteristics of the RPE were evaluated using confocal microscopy and immunocytochemistry. The rates of fluid flow across iPSC-RPE monolayer were measured to compare apical to basal fluid transports by RPE. RNA sequencing was performed on iPSC-RPE to identify the differences in gene expression profiles, and specific gene sets were tested using Gene Set Enrichment Analysis. RESULTS: Morphological characteristics, gene expression, and epithelial integrity of ARB iPSC were comparable to those of BD patient or normal control. Fluid transport from apical to basal was significantly decreased in ARB iPSC-RPE compared with BD iPSC-RPE or control iPSC-RPE. Gene Set Enrichment Analysis confirmed that ARB iPSC-RPE exhibited significant enrichments of epithelial-mesenchymal transition gene set and TNF-α signaling via NF-κB gene set compared to control iPSC-RPE or BD iPSC-RPE. CONCLUSION: A human iPSC model of ARB showed a functional deficiency rather than anatomical defects. ARB may be caused by RPE dysfunction following BEST1 mutation.


Assuntos
Bestrofinas/genética , Oftalmopatias Hereditárias/genética , Células-Tronco Pluripotentes Induzidas , Doenças Retinianas/genética , Epitélio Pigmentado da Retina , Distrofia Macular Viteliforme/genética , Distrofia Macular Viteliforme/fisiopatologia , Diferenciação Celular , Canais de Cloreto/genética , Canais de Cloreto/metabolismo , Oftalmopatias Hereditárias/diagnóstico , Oftalmopatias Hereditárias/metabolismo , Oftalmopatias Hereditárias/patologia , Expressão Gênica , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Doenças Retinianas/diagnóstico , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/fisiopatologia , Transtornos da Visão , Acuidade Visual , Distrofia Macular Viteliforme/metabolismo
3.
Nat Commun ; 11(1): 4038, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32788587

RESUMO

Asparaginyl-tRNA synthetase1 (NARS1) is a member of the ubiquitously expressed cytoplasmic Class IIa family of tRNA synthetases required for protein translation. Here, we identify biallelic missense and frameshift mutations in NARS1 in seven patients from three unrelated families with microcephaly and neurodevelopmental delay. Patient cells show reduced NARS1 protein, impaired NARS1 activity and impaired global protein synthesis. Cortical brain organoid modeling shows reduced proliferation of radial glial cells (RGCs), leading to smaller organoids characteristic of microcephaly. Single-cell analysis reveals altered constituents of both astrocytic and RGC lineages, suggesting a requirement for NARS1 in RGC proliferation. Our findings demonstrate that NARS1 is required to meet protein synthetic needs and to support RGC proliferation in human brain development.


Assuntos
Aspartato-tRNA Ligase/deficiência , Aspartato-tRNA Ligase/genética , Córtex Cerebral/patologia , Microcefalia/genética , Células-Tronco Neurais/patologia , Organoides/patologia , Aminoacil-RNA de Transferência/genética , Adolescente , Adulto , Sequência de Bases , Diferenciação Celular , Proliferação de Células , Tamanho Celular , Sobrevivência Celular , Criança , Família , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Antígeno Ki-67/metabolismo , Masculino , Mutação/genética , Células-Tronco Neurais/metabolismo , Neuroglia/metabolismo , Linhagem , Adulto Jovem
4.
Science ; 369(6503): 561-565, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32732423

RESUMO

Most neuropsychiatric disease risk variants are in noncoding sequences and lack functional interpretation. Because regulatory sequences often reside in open chromatin, we reasoned that neuropsychiatric disease risk variants may affect chromatin accessibility during neurodevelopment. Using human induced pluripotent stem cell (iPSC)-derived neurons that model developing brains, we identified thousands of genetic variants exhibiting allele-specific open chromatin (ASoC). These neuronal ASoCs were partially driven by altered transcription factor binding, overrepresented in brain gene enhancers and expression quantitative trait loci, and frequently associated with distal genes through chromatin contacts. ASoCs were enriched for genetic variants associated with brain disorders, enabling identification of functional schizophrenia risk variants and their cis-target genes. This study highlights ASoC as a functional mechanism of noncoding neuropsychiatric risk variants, providing a powerful framework for identifying disease causal variants and genes.


Assuntos
Alelos , Encéfalo/metabolismo , Cromatina/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Esquizofrenia/genética , Elementos Facilitadores Genéticos , Humanos , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Risco
5.
Nat Commun ; 11(1): 4178, 2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32826895

RESUMO

Friedreich's ataxia (FRDA) is an autosomal-recessive neurodegenerative and cardiac disorder which occurs when transcription of the FXN gene is silenced due to an excessive expansion of GAA repeats into its first intron. Herein, we generate dorsal root ganglia organoids (DRG organoids) by in vitro differentiation of human iPSCs. Bulk and single-cell RNA sequencing show that DRG organoids present a transcriptional signature similar to native DRGs and display the main peripheral sensory neuronal and glial cell subtypes. Furthermore, when co-cultured with human intrafusal muscle fibers, DRG organoid sensory neurons contact their peripheral targets and reconstitute the muscle spindle proprioceptive receptors. FRDA DRG organoids model some molecular and cellular deficits of the disease that are rescued when the entire FXN intron 1 is removed, and not with the excision of the expanded GAA tract. These results strongly suggest that removal of the repressed chromatin flanking the GAA tract might contribute to rescue FXN total expression and fully revert the pathological hallmarks of FRDA DRG neurons.


Assuntos
Ataxia de Friedreich/genética , Ataxia de Friedreich/patologia , Gânglios Espinais/metabolismo , Edição de Genes/métodos , Proteínas de Ligação ao Ferro/genética , Organoides/metabolismo , Células Receptoras Sensoriais/metabolismo , Antioxidantes/farmacologia , Sistemas CRISPR-Cas , Diferenciação Celular , Cromatina/metabolismo , Ataxia de Friedreich/tratamento farmacológico , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/patologia , Predisposição Genética para Doença/genética , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Íntrons , Mitocôndrias/metabolismo , Organoides/efeitos dos fármacos , Organoides/patologia , Células Receptoras Sensoriais/patologia , Análise de Sequência de RNA , Transcriptoma
6.
Nat Commun ; 11(1): 3881, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32753572

RESUMO

Cells typically respond to chemical or physical perturbations via complex signaling cascades which can simultaneously affect multiple physiological parameters, such as membrane voltage, calcium, pH, and redox potential. Protein-based fluorescent sensors can report many of these parameters, but spectral overlap prevents more than ~4 modalities from being recorded in parallel. Here we introduce the technique, MOSAIC, Multiplexed Optical Sensors in Arrayed Islands of Cells, where patterning of fluorescent sensor-encoding lentiviral vectors with a microarray printer enables parallel recording of multiple modalities. We demonstrate simultaneous recordings from 20 sensors in parallel in human embryonic kidney (HEK293) cells and in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), and we describe responses to metabolic and pharmacological perturbations. Together, these results show that MOSAIC can provide rich multi-modal data on complex physiological responses in multiple cell types.


Assuntos
Técnicas Biossensoriais/métodos , Células-Tronco Pluripotentes Induzidas/metabolismo , Microscopia de Fluorescência/métodos , Miócitos Cardíacos/metabolismo , Imagem Óptica/métodos , Potenciais de Ação/efeitos dos fármacos , Antagonistas Adrenérgicos beta/farmacologia , Técnicas Biossensoriais/instrumentação , Cálcio/química , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Peróxido de Hidrogênio/farmacologia , Concentração de Íons de Hidrogênio , Células-Tronco Pluripotentes Induzidas/citologia , Mitocôndrias/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/fisiologia , Imagem Óptica/instrumentação , Oxidantes/farmacologia , Oxirredução/efeitos dos fármacos , Propanolaminas/farmacologia
7.
Nat Commun ; 11(1): 4110, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807790

RESUMO

Hutchinson-Gilford Progeria Syndrome (HGPS) is a premature aging disease in children that leads to early death. Smooth muscle cells (SMCs) are the most affected cells in HGPS individuals, although the reason for such vulnerability remains poorly understood. In this work, we develop a microfluidic chip formed by HGPS-SMCs generated from induced pluripotent stem cells (iPSCs), to study their vulnerability to flow shear stress. HGPS-iPSC SMCs cultured under arterial flow conditions detach from the chip after a few days of culture; this process is mediated by the upregulation of metalloprotease 13 (MMP13). Importantly, double-mutant LmnaG609G/G609GMmp13-/- mice or LmnaG609G/G609GMmp13+/+ mice treated with a MMP inhibitor show lower SMC loss in the aortic arch than controls. MMP13 upregulation appears to be mediated, at least in part, by the upregulation of glycocalyx. Our HGPS-SMCs chip represents a platform for developing treatments for HGPS individuals that may complement previous pre-clinical and clinical treatments.


Assuntos
Metaloproteinase 13 da Matriz/metabolismo , Miócitos de Músculo Liso/metabolismo , Animais , Biotecnologia/métodos , Doenças Cardiovasculares/metabolismo , Feminino , Frequência Cardíaca/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Lamina Tipo A/genética , Lamina Tipo A/metabolismo , Masculino , Inibidores de Metaloproteinases de Matriz/farmacologia , Camundongos , Camundongos Mutantes , Miócitos de Músculo Liso/efeitos dos fármacos , Progéria/metabolismo , Progéria/patologia , Proteômica/métodos
8.
Nat Commun ; 11(1): 3848, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737286

RESUMO

Amyotrophic Lateral Sclerosis (ALS) is a fatal disease characterized by the degeneration of upper and lower motor neurons (MNs). We find a significant reduction of the retromer complex subunit VPS35 in iPSCs-derived MNs from ALS patients, in MNs from ALS post mortem explants and in MNs from SOD1G93A mice. Being the retromer involved in trafficking of hydrolases, a pathological hallmark in ALS, we design, synthesize and characterize an array of retromer stabilizers based on bis-guanylhydrazones connected by a 1,3-phenyl ring linker. We select compound 2a as a potent and bioavailable interactor of VPS35-VPS29. Indeed, while increasing retromer stability in ALS mice, compound 2a attenuates locomotion impairment and increases MNs survival. Moreover, compound 2a increases VPS35 in iPSCs-derived MNs and shows brain bioavailability. Our results clearly suggest the retromer as a valuable druggable target in ALS.


Assuntos
Esclerose Amiotrófica Lateral/tratamento farmacológico , Hidrazonas/farmacologia , Neurônios Motores/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Proteínas de Transporte Vesicular/genética , Esclerose Amiotrófica Lateral/genética , Esclerose Amiotrófica Lateral/metabolismo , Esclerose Amiotrófica Lateral/patologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Diferenciação Celular , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Hidrazonas/síntese química , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Masculino , Camundongos , Camundongos Transgênicos , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/síntese química , Ligação Proteica/efeitos dos fármacos , Multimerização Proteica , Relação Estrutura-Atividade , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Proteínas de Transporte Vesicular/metabolismo
9.
Nat Commun ; 11(1): 3369, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32632153

RESUMO

Induced pluripotent stem cell (iPSC)-derived dopaminergic (DA) neurons are an expected source for cell-based therapies for Parkinson's disease (PD). The regulatory criteria for the clinical application of these therapies, however, have not been established. Here we show the results of our pre-clinical study, in which we evaluate the safety and efficacy of dopaminergic progenitors (DAPs) derived from a clinical-grade human iPSC line. We confirm the characteristics of DAPs by in vitro analyses. We also verify that the DAP population include no residual undifferentiated iPSCs or early neural stem cells and have no genetic aberration in cancer-related genes. Furthermore, in vivo studies using immunodeficient mice reveal no tumorigenicity or toxicity of the cells. When the DAPs are transplanted into the striatum of 6-OHDA-lesioned rats, the animals show behavioral improvement. Based on these results, we started a clinical trial to treat PD patients in 2018.


Assuntos
Neurônios Dopaminérgicos/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Neurais/transplante , Doença de Parkinson/terapia , Transplante de Células-Tronco/métodos , Animais , Diferenciação Celular/genética , Linhagem Celular , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Macaca fascicularis , Masculino , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Ratos Nus , Transplante Heterólogo
10.
Gene ; 758: 144958, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32683073

RESUMO

Short-lived therapeutic gene expression in mammalian cells by DNA methylation is one of the major challenges in gene therapy. In this study, we assessed the implication of DNA methylation on the duration of GFP expression in mouse embryonic stem (ES) and mouse induced pluripotent stem (iPS) cells. The cells were transduced with lentivirus (LV) carrying green fluorescent protein (GFP) driven by either human elongation factor (EF1α) or cytomegalovirus (CMV) promoter. Transduced iPS cells exhibited higher percentage of GFP+ cells with persistent mean fluorescent intensity than transduced ES cells. Analysis on the integrated copy of transgene in the population of the transduced cells demonstrated similar copy number. However, significant increase in GFP intensity following 5-azaC treatment was observed in transduced ES cells only, suggesting the influence of DNA methylation in transgene silencing. Subsequent DNA methylation analysis showed that the promoter and the GFP region of the provirus in iPS cells had negligible methylation profile compared to transduced ES cells. Interestingly, sustained transgene expression was observed upon directed differentiation of transduced iPS cells towards CD34+ CD45+ cells. Hence, this study has shown that favourable transgene activity from lentiviral transduced iPS cells was due to the lack of methylation at the proviral regions.


Assuntos
Metilação de DNA/genética , Células-Tronco Embrionárias/metabolismo , Proteínas de Fluorescência Verde/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Animais , Azacitidina/farmacologia , Linhagem Celular , Citomegalovirus/genética , Fator de Iniciação 1 em Eucariotos/genética , Regulação da Expressão Gênica/genética , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas/genética , Transdução Genética
11.
Proc Natl Acad Sci U S A ; 117(30): 17842-17853, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32669437

RESUMO

Stem cells are capable of unlimited proliferation but can be induced to form brain cells. Factors that specifically regulate human development are poorly understood. We found that human stem cells expressed high levels of the envelope protein of an endogenized human-specific retrovirus (HERV-K, HML-2) from loci in chromosomes 12 and 19. The envelope protein was expressed on the cell membrane of the stem cells and was critical in maintaining the stemness via interactions with CD98HC, leading to triggering of human-specific signaling pathways involving mammalian target of rapamycin (mTOR) and lysophosphatidylcholine acyltransferase (LPCAT1)-mediated epigenetic changes. Down-regulation or epigenetic silencing of HML-2 env resulted in dissociation of the stem cell colonies and enhanced differentiation along neuronal pathways. Thus HML-2 regulation is critical for human embryonic and neurodevelopment, while it's dysregulation may play a role in tumorigenesis and neurodegeneration.


Assuntos
Diferenciação Celular , Retrovirus Endógenos/fisiologia , Neurônios/metabolismo , Transdução de Sinais , Células-Tronco/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Biomarcadores , Diferenciação Celular/genética , Autorrenovação Celular/genética , Cadeia Pesada da Proteína-1 Reguladora de Fusão/metabolismo , Regulação Viral da Expressão Gênica , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurônios/citologia , Ligação Proteica , Células-Tronco/citologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas do Envelope Viral/genética
12.
Cell Stem Cell ; 27(1): 125-136.e7, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32579880

RESUMO

SARS-CoV-2 has caused the COVID-19 pandemic. There is an urgent need for physiological models to study SARS-CoV-2 infection using human disease-relevant cells. COVID-19 pathophysiology includes respiratory failure but involves other organ systems including gut, liver, heart, and pancreas. We present an experimental platform comprised of cell and organoid derivatives from human pluripotent stem cells (hPSCs). A Spike-enabled pseudo-entry virus infects pancreatic endocrine cells, liver organoids, cardiomyocytes, and dopaminergic neurons. Recent clinical studies show a strong association with COVID-19 and diabetes. We find that human pancreatic beta cells and liver organoids are highly permissive to SARS-CoV-2 infection, further validated using adult primary human islets and adult hepatocyte and cholangiocyte organoids. SARS-CoV-2 infection caused striking expression of chemokines, as also seen in primary human COVID-19 pulmonary autopsy samples. hPSC-derived cells/organoids provide valuable models for understanding the cellular responses of human tissues to SARS-CoV-2 infection and for disease modeling of COVID-19.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Modelos Biológicos , Organoides/virologia , Pneumonia Viral/virologia , Tropismo , Animais , Autopsia , Linhagem Celular , Infecções por Coronavirus/patologia , Hepatócitos/patologia , Hepatócitos/virologia , Humanos , Células-Tronco Pluripotentes Induzidas/virologia , Fígado/patologia , Camundongos , Pâncreas/patologia , Pâncreas/virologia , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/patologia , Internalização do Vírus
13.
Nat Commun ; 11(1): 2876, 2020 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-32513994

RESUMO

Precise gene editing aims at generating single-nucleotide modifications to correct or model human disease. However, precision editing with nucleases such as CRIPSR-Cas9 has seen limited success due to poor efficiency and limited practicality. Here, we establish a fluorescent DNA repair assay in human induced pluripotent stem (iPS) cells to visualize and quantify the frequency of DNA repair outcomes during monoallelic and biallelic targeting. We found that modulating both DNA repair and cell cycle phase via defined culture conditions and small molecules synergistically enhanced the frequency of homology-directed repair (HDR). Notably, targeting in homozygous reporter cells results in high levels of editing with a vast majority of biallelic HDR outcomes. We then leverage efficient biallelic HDR with mixed ssODN repair templates to generate heterozygous mutations. Synergistic gene editing represents an effective strategy to generate precise genetic modifications in human iPS cells.


Assuntos
Ciclo Celular , Reparo do DNA , Edição de Genes , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Alelos , Sequência de Aminoácidos , Sequência de Bases , Resposta ao Choque Frio , Fluorescência , Loci Gênicos , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/metabolismo , Homozigoto , Humanos , Mutação/genética
14.
Mol Cell ; 79(1): 84-98.e9, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32526163

RESUMO

Rett syndrome (RTT), mainly caused by mutations in methyl-CpG binding protein 2 (MeCP2), is one of the most prevalent intellectual disorders without effective therapies. Here, we used 2D and 3D human brain cultures to investigate MeCP2 function. We found that MeCP2 mutations cause severe abnormalities in human interneurons (INs). Surprisingly, treatment with a BET inhibitor, JQ1, rescued the molecular and functional phenotypes of MeCP2 mutant INs. We uncovered that abnormal increases in chromatin binding of BRD4 and enhancer-promoter interactions underlie the abnormal transcription in MeCP2 mutant INs, which were recovered to normal levels by JQ1. We revealed cell-type-specific transcriptome impairment in MeCP2 mutant region-specific human brain organoids that were rescued by JQ1. Finally, JQ1 ameliorated RTT-like phenotypes in mice. These data demonstrate that BRD4 dysregulation is a critical driver for RTT etiology and suggest that targeting BRD4 could be a potential therapeutic opportunity for RTT.


Assuntos
Azepinas/farmacologia , Encéfalo/patologia , Proteínas de Ciclo Celular/metabolismo , Interneurônios/patologia , Proteína 2 de Ligação a Metil-CpG/fisiologia , Síndrome de Rett/patologia , Fatores de Transcrição/metabolismo , Transcriptoma/efeitos dos fármacos , Triazóis/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Proteínas de Ciclo Celular/genética , Feminino , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Embrionárias Humanas/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Interneurônios/efeitos dos fármacos , Interneurônios/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Fenótipo , Síndrome de Rett/tratamento farmacológico , Síndrome de Rett/genética , Síndrome de Rett/metabolismo , Fatores de Transcrição/genética
15.
J Vis Exp ; (160)2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32597877

RESUMO

The current protocol describes methods to generate scalable, mesh-shaped engineered cardiac tissues (ECTs) composed of cardiovascular cells derived from human induced pluripotent stem cells (hiPSCs), which are developed towards the goal of clinical use. HiPSC-derived cardiomyocytes, endothelial cells, and vascular mural cells are mixed with gel matrix and then poured into a polydimethylsiloxane (PDMS) tissue mold with rectangular internal staggered posts. By culture day 14 ECTs mature into a 1.5 cm x 1.5 cm mesh structure with 0.5 mm diameter myofiber bundles. Cardiomyocytes align to the long-axis of each bundle and spontaneously beat synchronously. This approach can be scaled up to a larger (3.0 cm x 3.0 cm) mesh ECT while preserving construct maturation and function. Thus, mesh-shaped ECTs generated from hiPSC-derived cardiac cells may be feasible for cardiac regeneration paradigms.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Células Endoteliais/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Miocárdio/metabolismo , Engenharia Tecidual/métodos , Células Endoteliais/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia
16.
Hum Genomics ; 14(1): 25, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32591003

RESUMO

Human-induced pluripotent stem cells (hiPSCs) and CRISPR/Cas9 gene editing system represent two instruments of basic and translational research, which both allow to acquire deep insight about the molecular bases of many diseases but also to develop pharmacological research.This review is focused to draw up the latest technique of gene editing applied on hiPSCs, exploiting some of the genetic manipulation directed to the discovery of innovative therapeutic strategies. There are many expediencies provided by the use of hiPSCs, which can represent a disease model clinically relevant and predictive, with a great potential if associated to CRISPR/Cas9 technology, a gene editing tool powered by ease and precision never seen before.Here, we describe the possible applications of CRISPR/Cas9 to hiPSCs: from drug development to drug screening and from gene therapy to the induction of the immunological response to specific virus infection, such as HIV and SARS-Cov-2.


Assuntos
Sistemas CRISPR-Cas , Descoberta de Drogas , Edição de Genes , Terapia Genética , Células-Tronco Pluripotentes Induzidas/citologia , Viroses/terapia , Animais , Reprogramação Celular , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/transplante , Viroses/genética
17.
Mol Cell ; 79(3): 521-534.e15, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32592681

RESUMO

Genome-wide mapping of chromatin interactions at high resolution remains experimentally and computationally challenging. Here we used a low-input "easy Hi-C" protocol to map the 3D genome architecture in human neurogenesis and brain tissues and also demonstrated that a rigorous Hi-C bias-correction pipeline (HiCorr) can significantly improve the sensitivity and robustness of Hi-C loop identification at sub-TAD level, especially the enhancer-promoter (E-P) interactions. We used HiCorr to compare the high-resolution maps of chromatin interactions from 10 tissue or cell types with a focus on neurogenesis and brain tissues. We found that dynamic chromatin loops are better hallmarks for cellular differentiation than compartment switching. HiCorr allowed direct observation of cell-type- and differentiation-specific E-P aggregates spanning large neighborhoods, suggesting a mechanism that stabilizes enhancer contacts during development. Interestingly, we concluded that Hi-C loop outperforms eQTL in explaining neurological GWAS results, revealing a unique value of high-resolution 3D genome maps in elucidating the disease etiology.


Assuntos
Cromatina/metabolismo , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Genoma Humano , Neurogênese/genética , Regiões Promotoras Genéticas , Adulto , Linhagem Celular , Cérebro/citologia , Cérebro/crescimento & desenvolvimento , Cérebro/metabolismo , Cromatina/ultraestrutura , Mapeamento Cromossômico , Feto , Histonas/genética , Histonas/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteínas do Tecido Nervoso/classificação , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Neurônios/citologia , Neurônios/metabolismo , Lobo Temporal/citologia , Lobo Temporal/crescimento & desenvolvimento , Lobo Temporal/metabolismo , Fatores de Transcrição/classificação , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
18.
Nat Commun ; 11(1): 2997, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32561714

RESUMO

PIEZO2 is the essential transduction channel for touch discrimination, vibration, and proprioception. Mice and humans lacking Piezo2 experience severe mechanosensory and proprioceptive deficits and fail to develop tactile allodynia. Bradykinin, a proalgesic agent released during inflammation, potentiates PIEZO2 activity. Molecules that decrease PIEZO2 function could reduce heightened touch responses during inflammation. Here, we find that the dietary fatty acid margaric acid (MA) decreases PIEZO2 function in a dose-dependent manner. Chimera analyses demonstrate that the PIEZO2 beam is a key region tuning MA-mediated channel inhibition. MA reduces neuronal action potential firing elicited by mechanical stimuli in mice and rat neurons and counteracts PIEZO2 sensitization by bradykinin. Finally, we demonstrate that this saturated fatty acid decreases PIEZO2 currents in touch neurons derived from human induced pluripotent stem cells. Our findings report on a natural product that inhibits PIEZO2 function and counteracts neuronal mechanical sensitization and reveal a key region for channel inhibition.


Assuntos
Ácidos Graxos/administração & dosagem , Canais Iônicos/antagonistas & inibidores , Mecanotransdução Celular/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Propriocepção/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Algoritmos , Animais , Células Cultivadas , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/fisiologia , Canais Iônicos/genética , Canais Iônicos/metabolismo , Mecanotransdução Celular/genética , Mecanotransdução Celular/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Neurônios/fisiologia , Propriocepção/genética , Propriocepção/fisiologia , Ratos , Tato/efeitos dos fármacos , Tato/fisiologia
19.
J Vis Exp ; (159)2020 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-32538908

RESUMO

Vascular development is determined by the sequential expression of specific genes, which can be studied by performing in situ hybridization assays in zebrafish during different developmental stages. To investigate the role of endoglin(eng) in vessel formation during the development of hereditary hemorrhagic telangiectasia (HHT), morpholino-mediated targeted knockdown of eng in zebrafish are used to study its temporal expression and associated functions. Here, whole-mount in situ RNA hybridization (WISH) is employed for the analysis of eng and its downstream genes in zebrafish embryos. Also, tube formation assays are performed in HHT patient-derived induced pluripotent stem cell-differentiated endothelial cells (iPSC-ECs; with eng mutations). A specific signal amplifying system using the whole amount In Situ Hybridization - WISH provides higher resolution and lower background results compared to traditional methods. To obtain a better signal, the post-fixation time is adjusted to 30 min after probe hybridization. Because fluorescence staining is not sensitive in zebrafish embryos, it is replaced with diaminobezidine (DAB) staining here. In this protocol, HHT patient-derived iPSC lines containing an eng mutation are differentiated into endothelial cells. After coating a plate with basement membrane matrix for 30 min at 37 °C, iPSC-ECs are seeded as a monolayer into wells and kept at 37 °C for 3 h. Then, the tube length and number of branches are calculated using microscopic images. Thus, with this improved WISH protocol, it is shown that reduced eng expression affects endothelial progenitor formation in zebrafish embryos. This is further confirmed by tube formation assays using iPSC-ECs derived from a patient with HHT. These assays confirm the role for eng in early vascular development.


Assuntos
Sistema Cardiovascular/embriologia , Endoglina/fisiologia , Células Endoteliais , Hibridização In Situ/métodos , Animais , Endoglina/genética , Células Endoteliais/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Mutação , Tubo Neural , Ligação Proteica , Telangiectasia Hemorrágica Hereditária/patologia , Peixe-Zebra
20.
Neuron ; 107(3): 436-453.e12, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32485136

RESUMO

New methods for investigating human astrocytes are urgently needed, given their critical role in the central nervous system. Here we show that CD49f is a novel marker for human astrocytes, expressed in fetal and adult brains from healthy and diseased individuals. CD49f can be used to purify fetal astrocytes and human induced pluripotent stem cell (hiPSC)-derived astrocytes. We provide single-cell and bulk transcriptome analyses of CD49f+ hiPSC-astrocytes and demonstrate that they perform key astrocytic functions in vitro, including trophic support of neurons, glutamate uptake, and phagocytosis. Notably, CD49f+ hiPSC-astrocytes respond to inflammatory stimuli, acquiring an A1-like reactive state, in which they display impaired phagocytosis and glutamate uptake and fail to support neuronal maturation. Most importantly, we show that conditioned medium from human reactive A1-like astrocytes is toxic to human and rodent neurons. CD49f+ hiPSC-astrocytes are thus a valuable resource for investigating human astrocyte function and dysfunction in health and disease.


Assuntos
Astrócitos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Integrina alfa6/metabolismo , Doença de Alzheimer/metabolismo , Animais , Astrócitos/fisiologia , Biomarcadores/metabolismo , Citometria de Fluxo , Perfilação da Expressão Gênica , Ácido Glutâmico/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/fisiopatologia , Camundongos , Técnicas de Patch-Clamp , Fagocitose/fisiologia , RNA-Seq , Análise de Célula Única
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