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1.
Nat Commun ; 12(1): 4321, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34262040

RESUMO

Symmetry establishment is a critical process in the development of multicellular organs and requires careful coordination of polarity axes while cells actively divide within tissues. Formation of the apical style in the Arabidopsis gynoecium involves a bilateral-to-radial symmetry transition, a stepwise process underpinned by the dynamic distribution of the plant morphogen auxin. Here we show that SPATULA (SPT) and the HECATE (HEC) bHLH proteins mediate the final step in the style radialisation process and synergistically control the expression of adaxial-identity genes, HOMEOBOX ARABIDOPSIS THALIANA 3 (HAT3) and ARABIDOPSIS THALIANA HOMEOBOX 4 (ATHB4). HAT3/ATHB4 module drives radialisation of the apical style by promoting basal-to-apical auxin flow and via a negative feedback mechanism that finetune auxin distribution through repression of SPT expression and cytokinin sensitivity. Thus, this work reveals the molecular basis of axes-coordination and hormonal cross-talk during the sequential steps of symmetry transition in the Arabidopsis style.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Homeodomínio/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Transporte Biológico , Citocininas/metabolismo , Retroalimentação Fisiológica , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/genética , Ácidos Indolacéticos/metabolismo
2.
Nat Commun ; 12(1): 3251, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059686

RESUMO

ALS is characterized by progressive inability to execute movements. Motor neurons innervating fast-twitch muscle-fibers preferentially degenerate. The reason for this differential vulnerability and its consequences on motor output is not known. Here, we uncover that fast motor neurons receive stronger inhibitory synaptic inputs than slow motor neurons, and disease progression in the SOD1G93A mouse model leads to specific loss of inhibitory synapses onto fast motor neurons. Inhibitory V1 interneurons show similar innervation pattern and loss of synapses. Moreover, from postnatal day 63, there is a loss of V1 interneurons in the SOD1G93A mouse. The V1 interneuron degeneration appears before motor neuron death and is paralleled by the development of a specific locomotor deficit affecting speed and limb coordination. This distinct ALS-induced locomotor deficit is phenocopied in wild-type mice but not in SOD1G93A mice after appearing of the locomotor phenotype when V1 spinal interneurons are silenced. Our study identifies a potential source of non-autonomous motor neuronal vulnerability in ALS and links ALS-induced changes in locomotor phenotype to inhibitory V1-interneurons.


Assuntos
Esclerose Amiotrófica Lateral/fisiopatologia , Interneurônios/patologia , Locomoção/fisiologia , Neurônios Motores/patologia , Esclerose Amiotrófica Lateral/genética , Esclerose Amiotrófica Lateral/patologia , Animais , Modelos Animais de Doenças , Feminino , Proteínas de Homeodomínio/metabolismo , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Fibras Musculares de Contração Rápida/fisiologia , Junção Neuromuscular/patologia , Junção Neuromuscular/fisiopatologia , Medula Espinal/citologia , Superóxido Dismutase/genética , Superóxido Dismutase-1/genética
3.
Nat Commun ; 12(1): 3354, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099670

RESUMO

Barrett's esophagus in gastrointestinal reflux patients constitutes a columnar epithelium with distal characteristics, prone to progress to esophageal adenocarcinoma. HOX genes are known mediators of position-dependent morphology. Here we show HOX collinearity in the adult gut while Barrett's esophagus shows high HOXA13 expression in stem cells and their progeny. HOXA13 overexpression appears sufficient to explain both the phenotype (through downregulation of the epidermal differentiation complex) and the oncogenic potential of Barrett's esophagus. Intriguingly, employing a mouse model that contains a reporter coupled to the HOXA13 promotor we identify single HOXA13-positive cells distally from the physiological esophagus, which is mirrored in human physiology, but increased in Barrett's esophagus. Additionally, we observe that HOXA13 expression confers a competitive advantage to cells. We thus propose that Barrett's esophagus and associated esophageal adenocarcinoma is the consequence of expansion of this gastro-esophageal HOXA13-expressing compartment following epithelial injury.


Assuntos
Esôfago de Barrett/genética , Carcinogênese/genética , Proteínas de Homeodomínio/genética , Oncogenes/genética , Adulto , Animais , Esôfago de Barrett/metabolismo , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/metabolismo , Trato Gastrointestinal/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Proteínas de Homeodomínio/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Família Multigênica/genética , RNA-Seq/métodos
4.
Aging (Albany NY) ; 13(12): 16786-16803, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162761

RESUMO

Gastric cancer (GC) is one of the most common aggressive cancers. The discovery of an effective biomarker is necessary for GC diagnosis. In this study, we confirmed that Paired box gene 4 (PAX4) is up-regulated in GC tissues and cells via quantitative real time polymerase chain reaction (qRT-PCR), western blot and immunohistochemical staining. It was also identified that PAX4 contributed to GC cell proliferation, migration and invasion through Cell Counting Kit-8, BrdU, flow cytometry assay, colony formation assay, transwell assays, and wound healing assay. miR-27b-3p was confirmed with the binding site with PAX4 using ChIP assay and served as a tumor suppressor that inhibiting GC cell growth and metastasis, and reversed the effect of PAX4. Bioinformatics prediction and dual luciferase assay results demonstrated that miR-27b-3p targeted Grb2, which could alter the function of miR-27b-3p. Furthermore, the transcriptional control of PAX4-regulated miR-27b-3p activated the Ras-ERK pathway. Taken together, the PAX4/miR-27b-3p/Grb2 loop is known to be involved in GC cell promotion, and can be seen as a promising target for GC therapy.


Assuntos
Progressão da Doença , Proteína Adaptadora GRB2/metabolismo , Proteínas de Homeodomínio/metabolismo , MicroRNAs/metabolismo , Fatores de Transcrição Box Pareados/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Animais , Apoptose/genética , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/genética , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Fatores de Transcrição Box Pareados/genética , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas ras/metabolismo
5.
Nat Commun ; 12(1): 3707, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140478

RESUMO

While the major drivers of melanoma initiation, including activation of NRAS/BRAF and loss of PTEN or CDKN2A, have been identified, the role of key transcription factors that impose altered transcriptional states in response to deregulated signaling is not well understood. The POU domain transcription factor BRN2 is a key regulator of melanoma invasion, yet its role in melanoma initiation remains unknown. Here, in a BrafV600E PtenF/+ context, we show that BRN2 haplo-insufficiency promotes melanoma initiation and metastasis. However, metastatic colonization is less efficient in the absence of Brn2. Mechanistically, BRN2 directly induces PTEN expression and in consequence represses PI3K signaling. Moreover, MITF, a BRN2 target, represses PTEN transcription. Collectively, our results suggest that on a PTEN heterozygous background somatic deletion of one BRN2 allele and temporal regulation of the other allele elicits melanoma initiation and progression.


Assuntos
Carcinogênese/metabolismo , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Genes Supressores de Tumor , Proteínas de Homeodomínio/metabolismo , Melanoma/metabolismo , Fatores do Domínio POU/metabolismo , Neoplasias Cutâneas/metabolismo , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Estudos de Coortes , Variações do Número de Cópias de DNA , Progressão da Doença , Técnicas de Silenciamento de Genes , Haploinsuficiência , Proteínas de Homeodomínio/genética , Humanos , Imuno-Histoquímica , Melanoma/genética , Melanoma/mortalidade , Melanoma/secundário , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Análise em Microsséries , Fator de Transcrição Associado à Microftalmia/metabolismo , Mutação , Fatores do Domínio POU/genética , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética , RNA Interferente Pequeno , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/secundário
6.
Nat Commun ; 12(1): 3708, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140506

RESUMO

3D genome alternations can dysregulate gene expression by rewiring enhancer-promoter interactions and lead to diseases. We report integrated analyses of 3D genome alterations and differential gene expressions in 18 newly diagnosed T-lineage acute lymphoblastic leukemia (T-ALL) patients and 4 healthy controls. 3D genome organizations at the levels of compartment, topologically associated domains and loop could hierarchically classify different subtypes of T-ALL according to T cell differentiation trajectory, similar to gene expressions-based classification. Thirty-four previously unrecognized translocations and 44 translocation-mediated neo-loops are mapped by Hi-C analysis. We find that neo-loops formed in the non-coding region of the genome could potentially regulate ectopic expressions of TLX3, TAL2 and HOXA transcription factors via enhancer hijacking. Importantly, both translocation-mediated neo-loops and NUP98-related fusions are associated with HOXA13 ectopic expressions. Patients with HOXA11-A13 expressions, but not other genes in the HOXA cluster, have immature immunophenotype and poor outcomes. Here, we highlight the potentially important roles of 3D genome alterations in the etiology and prognosis of T-ALL.


Assuntos
Cromossomos/metabolismo , Proteínas de Homeodomínio/genética , Leucemia-Linfoma de Células T do Adulto/genética , Conformação Molecular , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Linfócitos T/metabolismo , Translocação Genética , Acetilação , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linhagem Celular Tumoral , Linhagem da Célula , Criança , Sequenciamento de Cromatina por Imunoprecipitação , Cromossomos/genética , Progressão da Doença , Elementos Facilitadores Genéticos , Perfilação da Expressão Gênica , Regulação Leucêmica da Expressão Gênica/genética , Regulação Leucêmica da Expressão Gênica/imunologia , Ontologia Genética , Hematopoese/genética , Histonas/metabolismo , Proteínas de Homeodomínio/metabolismo , Humanos , Imunofenotipagem , Leucemia-Linfoma de Células T do Adulto/metabolismo , Leucemia-Linfoma de Células T do Adulto/mortalidade , Leucemia-Linfoma de Células T do Adulto/patologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Prognóstico , Linfócitos T/patologia , Adulto Jovem
7.
Science ; 372(6546): 1085-1091, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34083488

RESUMO

Whereas coding variants often have pleiotropic effects across multiple tissues, noncoding variants are thought to mediate their phenotypic effects by specific tissue and temporal regulation of gene expression. Here, we investigated the genetic and functional architecture of a genomic region within the FTO gene that is strongly associated with obesity risk. We show that multiple variants on a common haplotype modify the regulatory properties of several enhancers targeting IRX3 and IRX5 from megabase distances. We demonstrate that these enhancers affect gene expression in multiple tissues, including adipose and brain, and impart regulatory effects during a restricted temporal window. Our data indicate that the genetic architecture of disease-associated loci may involve extensive pleiotropy, allelic heterogeneity, shared allelic effects across tissues, and temporally restricted effects.


Assuntos
Tecido Adiposo/metabolismo , Encéfalo/metabolismo , Proteínas de Homeodomínio/genética , Obesidade/genética , Fatores de Transcrição/genética , Alelos , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Animais , Encéfalo/embriologia , Linhagem Celular , Cromatina/química , Cromatina/metabolismo , Desenvolvimento Embrionário , Elementos Facilitadores Genéticos , Comportamento Alimentar , Preferências Alimentares , Regulação da Expressão Gênica , Haplótipos , Proteínas de Homeodomínio/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Obesidade/fisiopatologia , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/metabolismo
8.
Nat Commun ; 12(1): 3330, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099664

RESUMO

Human pluripotent stem cell (hPSC)-derived pancreatic ß cells are an attractive cell source for treating diabetes. However, current derivation methods remain inefficient, heterogeneous, and cell line dependent. To address these issues, we first devised a strategy to efficiently cluster hPSC-derived pancreatic progenitors into 3D structures. Through a systematic study, we discovered 10 chemicals that not only retain the pancreatic progenitors in 3D clusters but also enhance their potentiality towards NKX6.1+/INS+ ß cells. We further systematically screened signaling pathway modulators in the three steps from pancreatic progenitors toward ß cells. The implementation of all these strategies and chemical combinations resulted in generating ß cells from different sources of hPSCs with high efficiency. The derived ß cells are functional and can reverse hyperglycemia in mice within two weeks. Our protocol provides a robust platform for studying human ß cells and developing hPSC-derived ß cells for cell replacement therapy.


Assuntos
Proteínas de Homeodomínio/metabolismo , Células Secretoras de Insulina/metabolismo , Pâncreas/metabolismo , Células-Tronco Pluripotentes/metabolismo , Animais , Diferenciação Celular/fisiologia , Linhagem Celular , Terapia Baseada em Transplante de Células e Tecidos , Diabetes Mellitus/metabolismo , Diabetes Mellitus Experimental , Proteínas de Homeodomínio/genética , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Transdução de Sinais
9.
Nat Commun ; 12(1): 3385, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099679

RESUMO

Obesity is the key driver of peripheral insulin resistance, one of the key features of type 2 diabetes (T2D). In insulin-resistant individuals, the expansion of beta-cell mass is able to delay or even prevent the onset of overt T2D. Here, we report that beta-arrestin-1 (barr1), an intracellular protein known to regulate signaling through G protein-coupled receptors, is essential for beta-cell replication and function in insulin-resistant mice maintained on an obesogenic diet. Specifically, insulin-resistant beta-cell-specific barr1 knockout mice display marked reductions in beta-cell mass and the rate of beta-cell proliferation, associated with pronounced impairments in glucose homeostasis. Mechanistic studies suggest that the observed metabolic deficits are due to reduced Pdx1 expression levels caused by beta-cell barr1 deficiency. These findings indicate that strategies aimed at enhancing barr1 activity and/or expression in beta-cells may prove useful to restore proper glucose homeostasis in T2D.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Células Secretoras de Insulina/patologia , Obesidade/metabolismo , beta-Arrestina 1/metabolismo , Animais , Glicemia/metabolismo , Proliferação de Células , Diabetes Mellitus Tipo 2/patologia , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Proteínas de Homeodomínio/metabolismo , Humanos , Resistência à Insulina , Masculino , Camundongos , Camundongos Knockout , Obesidade/etiologia , Obesidade/patologia , Transativadores/metabolismo , beta-Arrestina 1/genética
10.
Nat Commun ; 12(1): 2861, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001891

RESUMO

Hair cells detect sound, head position or water movements when their mechanosensory hair bundle is deflected. Each hair bundle has an asymmetric architecture that restricts stimulus detection to a single axis. Coordinated hair cell orientations within sensory epithelia further tune stimulus detection at the organ level. Here, we identify GPR156, an orphan GPCR of unknown function, as a critical regulator of hair cell orientation. We demonstrate that the transcription factor EMX2 polarizes GPR156 distribution, enabling it to signal through Gαi and trigger a 180° reversal in hair cell orientation. GPR156-Gαi mediated reversal is essential to establish hair cells with mirror-image orientations in mouse otolith organs in the vestibular system and in zebrafish lateral line. Remarkably, GPR156-Gαi also instructs hair cell reversal in the auditory epithelium, despite a lack of mirror-image organization. Overall, our work demonstrates that conserved GPR156-Gαi signaling is integral to the framework that builds directional responses into mechanosensory epithelia.


Assuntos
Epitélio/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Células Ciliadas Auditivas/metabolismo , Proteínas de Homeodomínio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Fatores de Transcrição/metabolismo , Animais , Polaridade Celular/genética , Feminino , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Células Ciliadas Auditivas/citologia , Proteínas de Homeodomínio/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Microscopia Confocal/métodos , Receptores Acoplados a Proteínas G/genética , Fatores de Transcrição/genética , Peixe-Zebra/metabolismo
11.
Nat Commun ; 12(1): 2892, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001903

RESUMO

Flying insects have invaded all the aerial space on Earth and this astonishing radiation could not have been possible without a remarkable morphological diversification of their flight appendages. Here, we show that characteristic spatial expression profiles and levels of the Hox genes Antennapedia (Antp) and Ultrabithorax (Ubx) underlie the formation of two different flight organs in the fruit fly Drosophila melanogaster. We further demonstrate that flight appendage morphology is dependent on specific Hox doses. Interestingly, we find that wing morphology from evolutionary distant four-winged insect species is also associated with a differential expression of Antp and Ubx. We propose that variation in the spatial expression profile and dosage of Hox proteins is a major determinant of flight appendage diversification in Drosophila and possibly in other insect species during evolution.


Assuntos
Proteína do Homeodomínio de Antennapedia/genética , Proteínas de Drosophila/genética , Voo Animal , Proteínas de Homeodomínio/genética , Fatores de Transcrição/genética , Animais , Proteína do Homeodomínio de Antennapedia/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Dosagem de Genes , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição/metabolismo , Asas de Animais/anatomia & histologia , Asas de Animais/metabolismo
12.
Nat Commun ; 12(1): 3086, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34035267

RESUMO

Meis1 and Meis2 are homeodomain transcription factors that regulate organogenesis through cooperation with Hox proteins. Elimination of Meis genes after limb induction has shown their role in limb proximo-distal patterning; however, limb development in the complete absence of Meis function has not been studied. Here, we report that Meis1/2 inactivation in the lateral plate mesoderm of mouse embryos leads to limb agenesis. Meis and Tbx factors converge in this function, extensively co-binding with Tbx to genomic sites and co-regulating enhancers of Fgf10, a critical factor in limb initiation. Limbs with three deleted Meis alleles show proximal-specific skeletal hypoplasia and agenesis of posterior skeletal elements. This failure in posterior specification results from an early role of Meis factors in establishing the limb antero-posterior prepattern required for Shh activation. Our results demonstrate roles for Meis transcription factors in early limb development and identify their involvement in previously undescribed interaction networks that regulate organogenesis.


Assuntos
Padronização Corporal/genética , Proteínas de Homeodomínio/genética , Botões de Extremidades/metabolismo , Proteína Meis1/genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fator 10 de Crescimento de Fibroblastos/genética , Fator 10 de Crescimento de Fibroblastos/metabolismo , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Proteínas de Homeodomínio/metabolismo , Botões de Extremidades/embriologia , Camundongos Knockout , Camundongos Transgênicos , Modelos Genéticos , Proteína Meis1/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional/genética
13.
Nat Commun ; 12(1): 2482, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33931647

RESUMO

While oncogenes promote tumorigenesis, they also induce deleterious cellular stresses, such as apoptosis, that cancer cells must combat by coopting adaptive responses. Whether tumor suppressor gene haploinsufficiency leads to such phenomena and their mechanistic basis is unclear. Here, we demonstrate that elevated levels of the anti-apoptotic factor, CASP8 and FADD-like apoptosis regulator (CFLAR), promotes apoptosis evasion in acute myeloid leukemia (AML) cells haploinsufficient for the cut-like homeobox 1 (CUX1) transcription factor, whose loss is associated with dismal clinical prognosis. Genome-wide CRISPR/Cas9 screening identifies CFLAR as a selective, acquired vulnerability in CUX1-deficient AML, which can be mimicked therapeutically using inhibitor of apoptosis (IAP) antagonists in murine and human AML cells. Mechanistically, CUX1 deficiency directly alleviates CUX1 repression of the CFLAR promoter to drive CFLAR expression and leukemia survival. These data establish how haploinsufficiency of a tumor suppressor is sufficient to induce advantageous anti-apoptosis cell survival pathways and concurrently nominate CFLAR as potential therapeutic target in these poor-prognosis leukemias.


Assuntos
Apoptose/genética , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Haploinsuficiência , Proteínas de Homeodomínio/metabolismo , Leucemia Mieloide Aguda/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Sobrevivência Celular/genética , Imunoprecipitação da Cromatina , Dipeptídeos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ontologia Genética , Genes Supressores de Tumor , Células-Tronco Hematopoéticas/metabolismo , Proteínas de Homeodomínio/genética , Humanos , Indóis/farmacologia , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Leucemia Mielomonocítica Crônica/genética , Leucemia Mielomonocítica Crônica/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Regiões Promotoras Genéticas , Análise Serial de Proteínas , Proteínas Repressoras/deficiência , Proteínas Repressoras/genética , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo
14.
Redox Biol ; 43: 102008, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34030118

RESUMO

Muscles of patients with facioscapulohumeral dystrophy (FSHD) are characterized by sporadic DUX4 expression and oxidative stress which is at least partially induced by DUX4 protein. Nevertheless, targeting oxidative stress with antioxidants has a limited impact on FSHD patients, and the exact role of oxidative stress in the pathology of FSHD, as well as its interplay with the DUX4 expression, remain unclear. Here we set up a screen for genes that are upregulated by DUX4 via oxidative stress with the aim to target these genes rather than the oxidative stress itself. Immortalized human myoblasts expressing DUX4 (MB135-DUX4) have an increased level of reactive oxygen species (ROS) and exhibit differentiation defects which can be reduced by treating the cells with classic (Tempol) or mitochondria-targeted antioxidants (SkQ1). The transcriptome analysis of antioxidant-treated MB135 and MB135-DUX4 myoblasts allowed us to identify 200 genes with expression deregulated by DUX4 but normalized upon antioxidant treatment. Several of these genes, including PITX1, have been already associated with FSHD and/or muscle differentiation. We confirmed that PITX1 was indeed deregulated in MB135-DUX4 cells and primary FSHD myoblasts and revealed a redox component in PITX1 regulation. PITX1 silencing partially reversed the differentiation defects of MB135-DUX4 myoblasts. Our approach can be used to identify and target redox-dependent genes involved in human diseases.


Assuntos
Distrofia Muscular Facioescapuloumeral , Diferenciação Celular , Proteínas de Homeodomínio/metabolismo , Humanos , Mioblastos/metabolismo , Estresse Oxidativo
15.
Cancer Sci ; 112(7): 2679-2691, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33949040

RESUMO

BCR-ABL1 gene fusion associated with additional DNA lesions involves the pathogenesis of chronic myelogenous leukemia (CML) from a chronic phase (CP) to a blast crisis of B lymphoid (CML-LBC) lineage and BCR-ABL1+ acute lymphoblastic leukemia (BCR-ABL1+ ALL). The recombination-activating gene RAG1 and RAG2 (collectively, RAG) proteins that assemble a diverse set of antigen receptor genes during lymphocyte development are abnormally expressed in CML-LBC and BCR-ABL1+ ALL. However, the direct involvement of dysregulated RAG in disease progression remains unclear. Here, we generate human wild-type (WT) RAG and catalytically inactive RAG-expressing BCR-ABL1+ and BCR-ABL1- cell lines, respectively, and demonstrate that BCR-ABL1 specifically collaborates with RAG recombinase to promote cell survival in vitro and in xenograft mice models. WT RAG-expressing BCR-ABL1+ cell lines and primary CD34+ bone marrow cells from CML-LBC samples maintain more double-strand breaks (DSB) compared to catalytically inactive RAG-expressing BCR-ABL1+ cell lines and RAG-deficient CML-CP samples, which are measured by γ-H2AX. WT RAG-expressing BCR-ABL1+ cells are biased to repair RAG-mediated DSB by the alternative non-homologous end joining pathway (a-NHEJ), which could contribute genomic instability through increasing the expression of a-NHEJ-related MRE11 and RAD50 proteins. As a result, RAG-expressing BCR-ABL1+ cells decrease sensitivity to tyrosine kinase inhibitors (TKI) by activating BCR-ABL1 signaling but independent of the levels of BCR-ABL1 expression and mutations in the BCR-ABL1 tyrosine kinase domain. These findings identify a surprising and novel role of RAG in the functional specialization of disease progression in BCR-ABL1+ leukemia through its endonuclease activity.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Proteínas de Fusão bcr-abl/metabolismo , Proteínas de Homeodomínio/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Proteínas Nucleares/metabolismo , Hidrolases Anidrido Ácido/metabolismo , Animais , Crise Blástica/genética , Crise Blástica/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Quebras de DNA de Cadeia Dupla , Reparo do DNA por Junção de Extremidades , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Progressão da Doença , Proteínas de Fusão bcr-abl/genética , Instabilidade Genômica , Xenoenxertos , Histonas/análise , Proteínas de Homeodomínio/genética , Humanos , Técnicas In Vitro , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Proteína Homóloga a MRE11/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico
16.
Anticancer Res ; 41(4): 1841-1847, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33813389

RESUMO

BACKGROUND/AIM: Homeobox A9 (HOXA9), a transcription factor regulating haematopoiesis and leukaemia cell proliferation, is suggested as a driver of acute myeloid leukaemia (AML). The aim of this study was to examine the effects of a synthetic HOXA9 inhibitor DB818 on AML cells in vitro. MATERIALS AND METHODS: AML cell lines OCI/AML3, MV4-11, and THP-1 with gene mutations up-regulating HOXA9 expression were treated with DB818 and analysed for cell proliferation and gene expression. The effects of HOXA9 knockdown were also evaluated. RESULTS: In the three AML cell lines, DB818 suppressed growth, induced apoptosis, and down-regulated the expression of HOXA9 transcriptional target genes: MYB proto-oncogene, transcription factor (MYB), MYC proto-oncogene, bHLH transcription factor (MYC), and BCL2 apoptosis regulator (BCL2), while up-regulating that of Fos proto-oncogene, AP-1 transcription factor subunit (FOS). HOXA9 knockdown showed similar effects, except for MYC expression, which differed between DB818-treated and HOXA9-deficient OCI/AML3 cells, suggesting an off-target effect of DB818. CONCLUSION: DB818 has potential as a novel molecular targeted drug for treating AML associated with HOXA9 overexpression.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Proteínas de Homeodomínio/antagonistas & inibidores , Leucemia Mieloide Aguda/tratamento farmacológico , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Regulação Leucêmica da Expressão Gênica , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Transdução de Sinais , Células THP-1
17.
BMC Plant Biol ; 21(1): 173, 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33838661

RESUMO

BACKGROUND: The shedding of premature sweet cherry (Prunus avium L) fruitlet has significantly impacted production, which in turn has a consequential effect on economic benefits. RESULT: To better understand the molecular mechanism of sweet cherry fruitlet abscission, pollen viability and structure had been observed from the pollination trees. Subsequently, the morphological characters of the shedding fruitlet, the plant hormone titers of dropping carpopodium, the transcriptome of the abscising carpopodium, as well as the HD-ZIP gene family were investigated. These findings showed that the pollens giving rise to heavy fruitlet abscission were malformed in structure, and their viability was lower than the average level. The abscising fruitlet and carpopodium were characterized in red color, and embryos of abscising fruitlet were aborted, which was highly ascribed to the low pollen viability and malformation. Transcriptome analysis showed 6462 were significantly differentially expressed, of which 2456 genes were up-regulated and 4006 down-regulated in the abscising carpopodium. Among these genes, the auxin biosynthesis and signal transduction genes (α-Trp, AUX1), were down-regulated, while the 1-aminocyclopropane-1-carboxylate oxidase gene (ACO) affected in ethylene biosynthesis, was up-regulated in abscising carpopodium. About genes related to cell wall remodeling (CEL, PAL, PG EXP, XTH), were up-regulated in carpopodium abscission, which reflecting the key roles in regulating the abscission process. The results of transcriptome analysis considerably conformed with those of proteome analysis as documented previously. In comparison with those of the retention fruitlet, the auxin contents in abscising carpopodium were significantly low, which presumably increased the ethylene sensitivity of the abscission zone, conversely, the abscisic acid (ABA) accumulation was considerably higher in abscising carpopodium. Furthermore, the ratio of (TZ + IAA + GA3) / ABA also obviously lower in abscising carpopodium. Besides, the HD-ZIP gene family analysis showed that PavHB16 and PavHB18 were up-regulated in abscising organs. CONCLUSION: Our findings combine morphology, cytology and transcriptional regulation to reveal the molecular mechanism of sweet cherry fruitlet abscission. It provides a new perspective for further study of plant organ shedding.


Assuntos
Frutas/crescimento & desenvolvimento , Genes de Plantas , Proteínas de Homeodomínio/genética , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Prunus avium/genética , Transcriptoma , Proteínas de Homeodomínio/metabolismo , Família Multigênica , Proteínas de Plantas/metabolismo , Prunus avium/crescimento & desenvolvimento
18.
Int J Mol Sci ; 22(9)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33924850

RESUMO

The chromosomal translocation t(4;11) marks an infant acute lymphoblastic leukemia associated with dismal prognosis. This rearrangement leads to the synthesis of the MLL-AF4 chimera, which exerts its oncogenic activity by upregulating transcription of genes involved in hematopoietic differentiation. Crucial for chimera's aberrant activity is the recruitment of the AF4/ENL/P-TEFb protein complex. Interestingly, a molecular interactor of AF4 is fibroblast growth factor receptor 2 (FGFR2). We herein analyze the role of FGFR2 in the context of leukemia using t(4;11) leukemia cell lines. We revealed the interaction between MLL-AF4 and FGFR2 by immunoprecipitation, western blot, and immunofluorescence experiments; we also tested the effects of FGFR2 knockdown, FGFR2 inhibition, and FGFR2 stimulation on the expression of the main MLL-AF4 target genes, i.e., HOXA9 and MEIS1. Our results show that FGFR2 and MLL-AF4 interact in the nucleus of leukemia cells and that FGFR2 knockdown, which is associated with decreased expression of HOXA9 and MEIS1, impairs the binding of MLL-AF4 to the HOXA9 promoter. We also show that stimulation of leukemia cells with FGF2 increases nuclear level of FGFR2 in its phosphorylated form, as well as HOXA9 and MEIS1 expression. In contrast, preincubation with the ATP-mimetic inhibitor PD173074, before FGF2 stimulation, reduced FGFR2 nuclear amount and HOXA9 and MEIS1 transcript level, thereby indicating that MLL-AF4 aberrant activity depends on the nuclear availability of FGFR2. Overall, our study identifies FGFR2 as a new and promising therapeutic target in t(4;11) leukemia.


Assuntos
Proteínas de Homeodomínio/metabolismo , Proteína de Leucina Linfoide-Mieloide/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Linhagem Celular Tumoral , Fator 2 de Crescimento de Fibroblastos , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocação Genética
19.
Int J Mol Sci ; 22(8)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33924205

RESUMO

Cancer stem cells (CSCs) play an important role in cancer recurrence and metastasis. It is suggested that the CSC properties in heterogeneous cancer cells can be induced by ionizing radiation (IR). This study investigated the role of DLX2 in the radioresistance and CSC properties induced by IR in NSCLC cancer cells. Here, A549 cells were exposed to fractionated irradiation at a cumulative dose of 52 Gy (4 Gy × 13 times) for a generation of radioresistant cells. After fractionated irradiation, surviving A549 cells exhibited resistance to IR and enhanced expression of various cancer stem cell markers. They also showed upregulation of mesenchymal molecular markers and downregulation of epithelial molecular markers, correlating with an increase in the migration and invasion. Fractionated irradiation triggered the secretion of TGF-ß1 and DLX2 expression. Interestingly, the increased DLX2 following fractionated irradiation seemed to induce the expression of the gene for the EGFR-ligand betacellulin via Smad2/3 signaling. To contrast, DLX2 knockdown dramatically decreased the expression of CSC markers, migration, and proliferation. Moreover, A549 cells expressing DLX2 shRNA formed tumors with a significantly smaller volume compared to those expressing control shDNA in a mouse xenograft assay. These results suggest that DLX2 overexpression in surviving NSCLC cancer cells after fractionated IR exposure is involved in the cancer stemness, radioresistance, EMT, tumor survival, and tumorigenic capability.


Assuntos
Autorrenovação Celular/efeitos da radiação , Raios gama , Proteínas de Homeodomínio/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/efeitos da radiação , Transdução de Sinais/efeitos da radiação , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Células A549 , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos da radiação , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Técnicas de Inativação de Genes , Humanos , Camundongos , Interferência de RNA , RNA Interferente Pequeno/genética , Tolerância a Radiação , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Science ; 372(6540)2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33888614

RESUMO

Skin scarring, the end result of adult wound healing, is detrimental to tissue form and function. Engrailed-1 lineage-positive fibroblasts (EPFs) are known to function in scarring, but Engrailed-1 lineage-negative fibroblasts (ENFs) remain poorly characterized. Using cell transplantation and transgenic mouse models, we identified a dermal ENF subpopulation that gives rise to postnatally derived EPFs by activating Engrailed-1 expression during adult wound healing. By studying ENF responses to substrate mechanics, we found that mechanical tension drives Engrailed-1 activation via canonical mechanotransduction signaling. Finally, we showed that blocking mechanotransduction signaling with either verteporfin, an inhibitor of Yes-associated protein (YAP), or fibroblast-specific transgenic YAP knockout prevents Engrailed-1 activation and promotes wound regeneration by ENFs, with recovery of skin appendages, ultrastructure, and mechanical strength. This finding suggests that there are two possible outcomes to postnatal wound healing: a fibrotic response (EPF-mediated) and a regenerative response (ENF-mediated).


Assuntos
Cicatriz/patologia , Fibroblastos/fisiologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Regeneração , Pele/lesões , Cicatrização , Animais , Cicatriz/prevenção & controle , Fibroblastos/transplante , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Mecanotransdução Celular , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-yes/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-yes/genética , Proteínas Proto-Oncogênicas c-yes/metabolismo , Transdução de Sinais , Estresse Mecânico , Ativação Transcricional , Transcriptoma , Verteporfina/farmacologia
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