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2.
Nat Immunol ; 17(5): 593-603, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26950238

RESUMO

Persistent viral infections are characterized by the simultaneous presence of chronic inflammation and T cell dysfunction. In prototypic models of chronicity--infection with human immunodeficiency virus (HIV) or lymphocytic choriomeningitis virus (LCMV)--we used transcriptome-based modeling to reveal that CD4(+) T cells were co-exposed not only to multiple inhibitory signals but also to tumor-necrosis factor (TNF). Blockade of TNF during chronic infection with LCMV abrogated the inhibitory gene-expression signature in CD4(+) T cells, including reduced expression of the inhibitory receptor PD-1, and reconstituted virus-specific immunity, which led to control of infection. Preventing signaling via the TNF receptor selectively in T cells sufficed to induce these effects. Targeted immunological interventions to disrupt the TNF-mediated link between chronic inflammation and T cell dysfunction might therefore lead to therapies to overcome persistent viral infection.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , HIV/imunologia , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Fator de Necrose Tumoral alfa/imunologia , Adolescente , Adulto , Idoso , Animais , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Citometria de Fluxo , Células HEK293 , HIV/fisiologia , Infecções por HIV/genética , Infecções por HIV/virologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Immunoblotting , Coriomeningite Linfocítica/genética , Coriomeningite Linfocítica/virologia , Vírus da Coriomeningite Linfocítica/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/imunologia , Receptores do Fator de Necrose Tumoral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética , Transcriptoma/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Adulto Jovem
3.
Nature ; 612(7940): 442-447, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36517713

RESUMO

Hybrid semiconductor-superconductor devices hold great promise for realizing topological quantum computing with Majorana zero modes1-5. However, multiple claims of Majorana detection, based on either tunnelling6-10 or Coulomb blockade (CB) spectroscopy11,12, remain disputed. Here we devise an experimental protocol that allows us to perform both types of measurement on the same hybrid island by adjusting its charging energy via tunable junctions to the normal leads. This method reduces ambiguities of Majorana detections by checking the consistency between CB spectroscopy and zero-bias peaks in non-blockaded transport. Specifically, we observe junction-dependent, even-odd modulated, single-electron CB peaks in InAs/Al hybrid nanowires without concomitant low-bias peaks in tunnelling spectroscopy. We provide a theoretical interpretation of the experimental observations in terms of low-energy, longitudinally confined island states rather than overlapping Majorana modes. Our results highlight the importance of combined measurements on the same device for the identification of topological Majorana zero modes.

4.
Nat Immunol ; 12(9): 898-907, 2011 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-21841785

RESUMO

Regulatory T cells (T(reg) cells) are essential for self-tolerance and immune homeostasis. Lack of effector T cell (T(eff) cell) function and gain of suppressive activity by T(reg) cells are dependent on the transcriptional program induced by Foxp3. Here we report that repression of SATB1, a genome organizer that regulates chromatin structure and gene expression, was crucial for the phenotype and function of T(reg) cells. Foxp3, acting as a transcriptional repressor, directly suppressed the SATB1 locus and indirectly suppressed it through the induction of microRNAs that bound the SATB1 3' untranslated region. Release of SATB1 from the control of Foxp3 in T(reg) cells caused loss of suppressive function, establishment of transcriptional T(eff) cell programs and induction of T(eff) cell cytokines. Our data support the proposal that inhibition of SATB1-mediated modulation of global chromatin remodeling is pivotal for maintaining T(reg) cell functionality.


Assuntos
Montagem e Desmontagem da Cromatina/imunologia , Fatores de Transcrição Forkhead/imunologia , Regulação da Expressão Gênica , Proteínas de Ligação à Região de Interação com a Matriz/imunologia , Tolerância a Antígenos Próprios , Linfócitos T Reguladores/imunologia , Regiões 3' não Traduzidas/genética , Regiões 3' não Traduzidas/imunologia , Animais , Diferenciação Celular/efeitos dos fármacos , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Citometria de Fluxo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Perfilação da Expressão Gênica , Genoma Humano , Estudo de Associação Genômica Ampla , Humanos , Lentivirus , Ativação Linfocitária/efeitos dos fármacos , Proteínas de Ligação à Região de Interação com a Matriz/genética , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/imunologia , MicroRNAs/metabolismo , MicroRNAs/farmacologia , Interferência de RNA , RNA Interferente Pequeno/imunologia , RNA Interferente Pequeno/metabolismo , RNA Interferente Pequeno/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tolerância a Antígenos Próprios/efeitos dos fármacos , Tolerância a Antígenos Próprios/genética , Tolerância a Antígenos Próprios/imunologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/metabolismo , Transdução Genética
5.
Nat Mater ; 20(8): 1106-1112, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34083775

RESUMO

Spin qubits are considered to be among the most promising candidates for building a quantum processor. Group IV hole spin qubits are particularly interesting owing to their ease of operation and compatibility with Si technology. In addition, Ge offers the option for monolithic superconductor-semiconductor integration. Here, we demonstrate a hole spin qubit operating at fields below 10 mT, the critical field of Al, by exploiting the large out-of-plane hole g-factors in planar Ge and by encoding the qubit into the singlet-triplet states of a double quantum dot. We observe electrically controlled g-factor difference-driven and exchange-driven rotations with tunable frequencies exceeding 100 MHz and dephasing times of 1 µs, which we extend beyond 150 µs using echo techniques. These results demonstrate that Ge hole singlet-triplet qubits are competing with state-of-the-art GaAs and Si singlet-triplet qubits. In addition, their rotation frequencies and coherence are comparable with those of Ge single spin qubits, but singlet-triplet qubits can be operated at much lower fields, emphasizing their potential for on-chip integration with superconducting technologies.

6.
Phys Rev Lett ; 128(12): 126803, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35394319

RESUMO

The spin-orbit interaction permits to control the state of a spin qubit via electric fields. For holes it is particularly strong, allowing for fast all electrical qubit manipulation, and yet an in-depth understanding of this interaction in hole systems is missing. Here we investigate, experimentally and theoretically, the effect of the cubic Rashba spin-orbit interaction on the mixing of the spin states by studying singlet-triplet oscillations in a planar Ge hole double quantum dot. Landau-Zener sweeps at different magnetic field directions allow us to disentangle the effects of the spin-orbit induced spin-flip term from those caused by strongly site-dependent and anisotropic quantum dot g tensors. Our work, therefore, provides new insights into the hole spin-orbit interaction, necessary for optimizing future qubit experiments.

7.
Br J Psychiatry ; : 1-10, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35225756

RESUMO

BACKGROUND: Response to lithium in patients with bipolar disorder is associated with clinical and transdiagnostic genetic factors. The predictive combination of these variables might help clinicians better predict which patients will respond to lithium treatment. AIMS: To use a combination of transdiagnostic genetic and clinical factors to predict lithium response in patients with bipolar disorder. METHOD: This study utilised genetic and clinical data (n = 1034) collected as part of the International Consortium on Lithium Genetics (ConLi+Gen) project. Polygenic risk scores (PRS) were computed for schizophrenia and major depressive disorder, and then combined with clinical variables using a cross-validated machine-learning regression approach. Unimodal, multimodal and genetically stratified models were trained and validated using ridge, elastic net and random forest regression on 692 patients with bipolar disorder from ten study sites using leave-site-out cross-validation. All models were then tested on an independent test set of 342 patients. The best performing models were then tested in a classification framework. RESULTS: The best performing linear model explained 5.1% (P = 0.0001) of variance in lithium response and was composed of clinical variables, PRS variables and interaction terms between them. The best performing non-linear model used only clinical variables and explained 8.1% (P = 0.0001) of variance in lithium response. A priori genomic stratification improved non-linear model performance to 13.7% (P = 0.0001) and improved the binary classification of lithium response. This model stratified patients based on their meta-polygenic loadings for major depressive disorder and schizophrenia and was then trained using clinical data. CONCLUSIONS: Using PRS to first stratify patients genetically and then train machine-learning models with clinical predictors led to large improvements in lithium response prediction. When used with other PRS and biological markers in the future this approach may help inform which patients are most likely to respond to lithium treatment.

8.
Anal Bioanal Chem ; 413(4): 987-998, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33215314

RESUMO

In the present study, a novel and reliable analytical method was developed and validated for the simultaneous determination of 1,3,5-tris(2,3-dibromopropyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione (TDBP-TAZTO) and 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine (TTBP-TAZ) in environmental samples using high-performance liquid chromatography coupled to a tandem mass spectrometer. Firstly, for optimization of the liquid chromatography separation, mobile phases, oven temperatures, modifiers, and buffers were varied. Afterwards, the extraction efficiency of sediment and fish samples was tested with different techniques (pressurized liquid, solid-liquid, ultrasound-assisted, and Soxhlet extraction). Additionally, cleanup using modified multilayer silica gel (sediment) and gel permeation chromatography as well as Florisil® columns (fish) with several solvent mixtures were performed. The best results were obtained with the pressurized liquid extraction (optimal conditions: extraction solvent 100% toluene, extraction time 20 min, cycles two, extraction temperature 100 °C, and flushing volume 60%) compared to other solvent extraction methods. On the basis of this optimized analytical procedure, the method was validated with satisfactory values of correlation coefficient (R2) between 0.998 and 0.999 for both matrices in the calibration range of 2.0-502.0 µg kg-1 for TDBP-TAZTO and 16.6-770.6 µg kg-1 for TTBP-TAZ in sediment samples as well as 4.8-303.5 µg kg-1 and 47.4-742.5 µg kg-1 in fish samples (bream), respectively. Mean recoveries (n = 5) were calculated for both analytes with spiked matrices at one concentration level (100 µg kg-1) between 98 and 114% with intra-day relative standard deviations less than 11%. The inter-day precision (n = 15) was also acceptable for both compounds < 11%. It was found that the limit of detection and limit of quantification were in the range of 0.4-1.3 µg kg-1 for TDBP-TAZTO and 10-28 µg kg-1 for TTBP-TAZ in surface sediment samples and 7-25 µg kg-1 and 22-80 µg kg-1 in fish samples (bream), respectively. The results indicated that these analytical methods could provide reliable and efficient approaches for quantification of TDBP-TAZTO and TTBP-TAZ in sediment and fish samples. Graphical abstract.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Retardadores de Chama/análise , Hidrocarbonetos Bromados/análise , Espectrometria de Massas em Tandem/métodos , Triazinas/análise , Poluentes Químicos da Água/análise , Animais , Monitoramento Ambiental/métodos , Peixes/metabolismo , Sedimentos Geológicos/análise , Halogenação , Limite de Detecção
9.
J Phycol ; 57(4): 1266-1283, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33751611

RESUMO

The biological communities of mountain lakes are suspected to be highly sensitive to global warming and associated catchment changes. To identify the parameters determining algal community responses, subfossil pigments from 21 different mountain lakes in the Bavarian-Tyrolean Limestone Alps were investigated. Sediment cores were radio-isotopically dated, and their pigment preservation evaluated. General additive models (GAM) of pigment compositions were calculated with temperature as the explanatory variable and generalized linear models with several lake parameters explaining log-transformed GAM P-values. Lake depth and trophic state were identified as major control variables of the algal community and productivity changes. Shifts in a deep oligotrophic alpine lake (lg(P) = -1.04) were half as strong as in a shallow mesotrophic alpine lake (lg(P) = -1.86) with faster warming and higher productivity forcing the development of biomass. Phytoplankton and macrophyte pigments increased clearly with warming, at lower altitudes, and decreased at the treeline, so that periphytic pigments dominated alpine sediments. This pattern is probably the result of interactions of UV radiation and allochthonous inputs of DOM. Our findings suggest that (sub)alpine shallow lakes with higher nutrient levels are most vulnerable to climate change-driven changes whereas deep, nutrient-poor lakes appear more resilient.


Assuntos
Ecossistema , Lagos , Biomassa , Mudança Climática , Fitoplâncton
10.
Am J Hum Genet ; 98(4): 755-62, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27018475

RESUMO

Nonsyndromic cleft lip with/without cleft palate (nsCL/P) and nonsyndromic cleft palate only (nsCPO) are the most frequent subphenotypes of orofacial clefts. A common syndromic form of orofacial clefting is Van der Woude syndrome (VWS) where individuals have CL/P or CPO, often but not always associated with lower lip pits. Recently, ∼5% of VWS-affected individuals were identified with mutations in the grainy head-like 3 gene (GRHL3). To investigate GRHL3 in nonsyndromic clefting, we sequenced its coding region in 576 Europeans with nsCL/P and 96 with nsCPO. Most strikingly, nsCPO-affected individuals had a higher minor allele frequency for rs41268753 (0.099) than control subjects (0.049; p = 1.24 × 10(-2)). This association was replicated in nsCPO/control cohorts from Latvia, Yemen, and the UK (pcombined = 2.63 × 10(-5); ORallelic = 2.46 [95% CI 1.6-3.7]) and reached genome-wide significance in combination with imputed data from a GWAS in nsCPO triads (p = 2.73 × 10(-9)). Notably, rs41268753 is not associated with nsCL/P (p = 0.45). rs41268753 encodes the highly conserved p.Thr454Met (c.1361C>T) (GERP = 5.3), which prediction programs denote as deleterious, has a CADD score of 29.6, and increases protein binding capacity in silico. Sequencing also revealed four novel truncating GRHL3 mutations including two that were de novo in four families, where all nine individuals harboring mutations had nsCPO. This is important for genetic counseling: given that VWS is rare compared to nsCPO, our data suggest that dominant GRHL3 mutations are more likely to cause nonsyndromic than syndromic CPO. Thus, with rare dominant mutations and a common risk variant in the coding region, we have identified an important contribution for GRHL3 in nsCPO.


Assuntos
Fissura Palatina/genética , Proteínas de Ligação a DNA/genética , Predisposição Genética para Doença , Fases de Leitura Aberta , Fatores de Transcrição/genética , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/genética , Alelos , Estudos de Casos e Controles , Fenda Labial/diagnóstico , Fenda Labial/genética , Fissura Palatina/diagnóstico , Cistos/diagnóstico , Cistos/genética , Humanos , Lábio/anormalidades , Mutação , Polimorfismo de Nucleotídeo Único , Grupos Raciais/genética
11.
PLoS Genet ; 12(3): e1005914, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26968009

RESUMO

Nonsyndromic orofacial clefts are common birth defects with multifactorial etiology. The most common type is cleft lip, which occurs with or without cleft palate (nsCLP and nsCLO, respectively). Although genetic components play an important role in nsCLP, the genetic factors that predispose to palate involvement are largely unknown. In this study, we carried out a meta-analysis on genetic and clinical data from three large cohorts and identified strong association between a region on chromosome 15q13 and nsCLP (P = 8.13 × 10(-14) for rs1258763; relative risk (RR): 1.46, 95% confidence interval (CI): 1.32-1.61)) but not nsCLO (P = 0.27; RR: 1.09 (0.94-1.27)). The 5 kb region of strongest association maps downstream of Gremlin-1 (GREM1), which encodes a secreted antagonist of the BMP4 pathway. We show during mouse embryogenesis, Grem1 is expressed in the developing lip and soft palate but not in the hard palate. This is consistent with genotype-phenotype correlations between rs1258763 and a specific nsCLP subphenotype, since a more than two-fold increase in risk was observed in patients displaying clefts of both the lip and soft palate but who had an intact hard palate (RR: 3.76, CI: 1.47-9.61, Pdiff<0.05). While we did not find lip or palate defects in Grem1-deficient mice, wild type embryonic palatal shelves developed divergent shapes when cultured in the presence of ectopic Grem1 protein (P = 0.0014). The present study identified a non-coding region at 15q13 as the second, genome-wide significant locus specific for nsCLP, after 13q31. Moreover, our data suggest that the closely located GREM1 gene contributes to a rare clinical nsCLP entity. This entity specifically involves abnormalities of the lip and soft palate, which develop at different time-points and in separate anatomical regions.


Assuntos
Encéfalo/anormalidades , Fenda Labial/genética , Fissura Palatina/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Peptídeos e Proteínas de Sinalização Intercelular/genética , Alelos , Animais , Encéfalo/patologia , Cromossomos Humanos Par 15 , Fenda Labial/patologia , Fissura Palatina/patologia , Genótipo , Humanos , Camundongos , População Branca
12.
Hum Genomics ; 11(1): 26, 2017 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-29122006

RESUMO

BACKGROUND: Lymphedema (LE) is a chronic clinical manifestation of filarial nematode infections characterized by lymphatic dysfunction and subsequent accumulation of protein-rich fluid in the interstitial space-lymphatic filariasis. A number of studies have identified single nucleotide polymorphisms (SNPs) associated with primary and secondary LE. To assess SNPs associated with LE caused by lymphatic filariasis, a cross-sectional study of unrelated Ghanaian volunteers was designed to genotype SNPs in 285 LE patients as cases and 682 infected patients without pathology as controls. One hundred thirty-one SNPs in 64 genes were genotyped. The genes were selected based on their roles in inflammatory processes, angiogenesis/lymphangiogenesis, and cell differentiation during tumorigenesis. RESULTS: Genetic associations with nominal significance were identified for five SNPs in three genes: vascular endothelial growth factor receptor-3 (VEGFR-3) rs75614493, two SNPs in matrix metalloprotease-2 (MMP-2) rs1030868 and rs2241145, and two SNPs in carcinoembryonic antigen-related cell adhesion molecule-1 (CEACAM-1) rs8110904 and rs8111171. Pathway analysis revealed an interplay of genes in the angiogenic/lymphangiogenic pathways. Plasma levels of both MMP-2 and CEACAM-1 were significantly higher in LE cases compared to controls. Functional characterization of the associated SNPs identified genotype GG of CEACAM-1 as the variant influencing the expression of plasma concentration, a novel finding observed in this study. CONCLUSION: The SNP associations found in the MMP-2, CEACAM-1, and VEGFR-3 genes indicate that angiogenic/lymphangiogenic pathways are important in LE clinical development.


Assuntos
Filariose Linfática/genética , Polimorfismo de Nucleotídeo Único , Wuchereria bancrofti/patogenicidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antígenos CD/sangue , Antígenos CD/genética , Estudos de Casos e Controles , Moléculas de Adesão Celular/sangue , Moléculas de Adesão Celular/genética , Estudos Transversais , Filariose Linfática/etiologia , Feminino , Frequência do Gene , Haplótipos , Interações Hospedeiro-Patógeno , Humanos , Masculino , Metaloproteinase 2 da Matriz/sangue , Metaloproteinase 2 da Matriz/genética , Pessoa de Meia-Idade , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/sangue , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/genética
13.
Nucleic Acids Res ; 44(22): 10631-10643, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27634931

RESUMO

There is a growing perception that long non-coding RNAs (lncRNAs) modulate cellular function. In this study, we analyzed the role of the lncRNA HOTAIR in mesenchymal stem cells (MSCs) with particular focus on senescence-associated changes in gene expression and DNA-methylation (DNAm). HOTAIR binding sites were enriched at genomic regions that become hypermethylated with increasing cell culture passage. Overexpression and knockdown of HOTAIR inhibited or stimulated adipogenic differentiation of MSCs, respectively. Modification of HOTAIR expression evoked only very moderate effects on gene expression, particularly of polycomb group target genes. Furthermore, overexpression and knockdown of HOTAIR resulted in DNAm changes at HOTAIR binding sites. Five potential triple helix forming domains were predicted within the HOTAIR sequence based on reverse Hoogsteen hydrogen bonds. Notably, the predicted triple helix target sites for these HOTAIR domains were also enriched in differentially expressed genes and close to DNAm changes upon modulation of HOTAIR Electrophoretic mobility shift assays provided further evidence that HOTAIR domains form RNA-DNA-DNA triplexes with predicted target sites. Our results demonstrate that HOTAIR impacts on differentiation of MSCs and that it is associated with senescence-associated DNAm. Targeting of epigenetic modifiers to relevant loci in the genome may involve triple helix formation with HOTAIR.


Assuntos
Células-Tronco Mesenquimais/fisiologia , RNA Longo não Codificante/fisiologia , Sequência de Bases , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Senescência Celular , Metilação de DNA , Epigênese Genética , Expressão Gênica , Humanos , Conformação de Ácido Nucleico , Ligação Proteica , RNA Longo não Codificante/química
14.
PLoS Genet ; 11(7): e1005415, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26226633

RESUMO

Type II germ cell cancers (GCC) can be subdivided into seminomas and non-seminomas. Seminomas are similar to carcinoma in situ (CIS) cells, the common precursor of type II GCCs, with regard to epigenetics and expression, while embryonal carcinomas (EC) are totipotent and differentiate into teratomas, yolk-sac tumors and choriocarcinomas. GCCs can present as seminomas with a non-seminoma component, raising the question if a CIS gives rise to seminomas and ECs at the same time or whether seminomas can be reprogrammed to ECs. In this study, we utilized the seminoma cell line TCam-2 that acquires an EC-like status after xenografting into the murine flank as a model for a seminoma to EC transition and screened for factors initiating and driving this process. Analysis of expression and DNA methylation dynamics during transition of TCam-2 revealed that many pluripotency- and reprogramming-associated genes were upregulated while seminoma-markers were downregulated. Changes in expression level of 53 genes inversely correlated to changes in DNA methylation. Interestingly, after xenotransplantation 6 genes (GDF3, NODAL, DNMT3B, DPPA3, GAL, AK3L1) were rapidly induced, followed by demethylation of their genomic loci, suggesting that these 6 genes are poised for expression driving the reprogramming. We demonstrate that inhibition of BMP signaling is the initial event in reprogramming, resulting in activation of the pluripotency-associated genes and NODAL signaling. We propose that reprogramming of seminomas to ECs is a multi-step process. Initially, the microenvironment causes inhibition of BMP signaling, leading to induction of NODAL signaling. During a maturation phase, a fast acting NODAL loop stimulates its own activity and temporarily inhibits BMP signaling. During the stabilization phase, a slow acting NODAL loop, involving WNTs re-establishes BMP signaling and the pluripotency circuitry. In parallel, DNMT3B-driven de novo methylation silences seminoma-associated genes and epigenetically fixes the EC state.


Assuntos
Proteínas Morfogenéticas Ósseas/genética , Carcinoma Embrionário/genética , Epigênese Genética , Proteína Nodal/genética , Seminoma/genética , Animais , Carcinoma Embrionário/patologia , Linhagem Celular Tumoral , Metilação de DNA/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Proteínas de Neoplasias/genética , Seminoma/patologia , Transdução de Sinais , Teratoma/genética , Teratoma/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Lancet ; 387(10023): 1085-1093, 2016 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-26806518

RESUMO

BACKGROUND: Lithium is a first-line treatment in bipolar disorder, but individual response is variable. Previous studies have suggested that lithium response is a heritable trait. However, no genetic markers of treatment response have been reproducibly identified. METHODS: Here, we report the results of a genome-wide association study of lithium response in 2563 patients collected by 22 participating sites from the International Consortium on Lithium Genetics (ConLiGen). Data from common single nucleotide polymorphisms (SNPs) were tested for association with categorical and continuous ratings of lithium response. Lithium response was measured using a well established scale (Alda scale). Genotyped SNPs were used to generate data at more than 6 million sites, using standard genomic imputation methods. Traits were regressed against genotype dosage. Results were combined across two batches by meta-analysis. FINDINGS: A single locus of four linked SNPs on chromosome 21 met genome-wide significance criteria for association with lithium response (rs79663003, p=1·37 × 10(-8); rs78015114, p=1·31 × 10(-8); rs74795342, p=3·31 × 10(-9); and rs75222709, p=3·50 × 10(-9)). In an independent, prospective study of 73 patients treated with lithium monotherapy for a period of up to 2 years, carriers of the response-associated alleles had a significantly lower rate of relapse than carriers of the alternate alleles (p=0·03268, hazard ratio 3·8, 95% CI 1·1-13·0). INTERPRETATION: The response-associated region contains two genes for long, non-coding RNAs (lncRNAs), AL157359.3 and AL157359.4. LncRNAs are increasingly appreciated as important regulators of gene expression, particularly in the CNS. Confirmed biomarkers of lithium response would constitute an important step forward in the clinical management of bipolar disorder. Further studies are needed to establish the biological context and potential clinical utility of these findings. FUNDING: Deutsche Forschungsgemeinschaft, National Institute of Mental Health Intramural Research Program.


Assuntos
Transtorno Bipolar/genética , Compostos de Lítio/uso terapêutico , Polimorfismo de Nucleotídeo Único/genética , Transtorno Bipolar/tratamento farmacológico , Feminino , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Estudos Prospectivos , Resultado do Tratamento
16.
Exp Dermatol ; 26(6): 536-541, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27306922

RESUMO

Alopecia areata (AA) is a common hair loss disorder of autoimmune aetiology, which often results in pronounced psychological distress. Understanding of the pathophysiology of AA is increasing, due in part to recent genetic findings implicating common variants at several genetic loci. To date, no study has investigated the contribution of copy number variants (CNVs) to AA, a prominent class of genomic variants involved in other autoimmune disorders. Here, we report a genomewide- and a candidate gene-focused CNV analysis performed in a cohort of 585 patients with AA and 1340 controls of Central European origin. A nominally significant association with AA was found for CNVs in the following five chromosomal regions: 4q35.2, 6q16.3, 9p23, 16p12.1 and 20p12.1. The most promising finding was a 342.5-kb associated region in 6q16.3 (duplications in 4/585 patients; 0/1340 controls). The duplications spanned the genes MCHR2 and MCHR2-AS1, implicated in melanin-concentrating hormone (MCH) signalling. These genes have not been implicated in previous studies of AA pathogenesis. However, previous research has shown that MCHR2 affects the scale colour of barfin flounder fish via the induction of melanin aggregation. AA preferentially affects pigmented hairs, and the hair of patients with AA frequently shows a change in colour when it regrows following an acute episode of AA. This might indicate a relationship between AA, pigmentation and MCH signalling. In conclusion, the present results provide suggestive evidence for the involvement of duplications in MCHR2 in AA pathogenesis.


Assuntos
Alopecia em Áreas/genética , Variações do Número de Cópias de DNA , Estudo de Associação Genômica Ampla , Receptores Acoplados a Proteínas G/genética , Receptores do Hormônio Hipofisário/genética , Adulto , Bélgica , Mapeamento Cromossômico , Estudos de Coortes , Europa (Continente) , Feminino , Genótipo , Alemanha , Humanos , Hormônios Hipotalâmicos/metabolismo , Masculino , Melaninas/metabolismo , Países Baixos , Pigmentação , Hormônios Hipofisários/metabolismo , Polimorfismo de Nucleotídeo Único , Transdução de Sinais
18.
Am J Med Genet B Neuropsychiatr Genet ; 174(4): 390-398, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28371232

RESUMO

The postsynaptic scaffolding protein SHANK3 is essential for the normal function of glutamatergic synapses in the brain. Emerging evidence suggests that impaired plasticity of glutamatergic synapses contributes to the pathology of schizophrenia (SCZ). To investigate whether variants in the SHANK3 gene contribute to the etiology of SCZ, we sequenced SHANK3 in 500 affected individuals (cohort C1). In total, we identified 48 variants and compared them to European controls from the 1000 Genomes Project and the Exome Variant Server. Five variants showed significant differences in frequencies between patients and controls. We were able to follow three of them up in an independent cohort (C2) comprising 993 SCZ patients and 932 German controls. We could not confirm an association for three of these variants (rs140201628, rs1557620, and rs61729471). Two rare variants with predicted functional relevance were identified in further SCZ individuals of cohort C1: c.3032G>T (p.G1011V) and c.*27C>T. The latter variant was found in one additional SCZ individual and the p.G1011V variant was identified in two additional SCZ individuals from cohort C2. The p.G1011V variant was the most interesting variant in our study; together with previous studies this variant has been identified in 4 out of 1,524 SCZ patients and in 4 out of 2,147 individuals with autism spectrum disorder (ASD), but not in 2468 European Sanger-sequenced controls. Therefore, we consider this variant a promising candidate variant for follow-up studies in larger samples and functional investigations. © 2017 Wiley Periodicals, Inc.


Assuntos
Exoma/genética , Mutação de Sentido Incorreto , Proteínas do Tecido Nervoso/genética , Esquizofrenia/genética , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Seguimentos , Predisposição Genética para Doença , Humanos , Masculino , Prognóstico , Esquizofrenia/patologia
19.
Neurobiol Dis ; 86: 121-30, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26631617

RESUMO

Temporal lobe epilepsy (TLE) is a severe brain disorder affecting particularly young adults. TLE is frequently associated with memory deterioration and neuronal damage of the hippocampal formation. It thereby reveals striking parallels to neurodegenerative disorders including Alzheimer's disease (AD). TLE patients differ with respect to their cognitive performance, but currently little is known about relevant molecular-genetic factors. Here, we correlated differential memory performance of pharmacoresistant TLE patients undergoing neurosurgery for seizure control with in-vitro findings of their hippocampal tissues. We analyzed mRNA transcripts and subsequently promoter variants specifically altered in brain tissue of individuals with 'very severe' memory impairment. TLE patients (n=79) were stratified according to preoperative memory impairment using an established four-tiered grading system ranging from 'average' to 'very severely'. Multimodal cluster analyses revealed molecules specifically associated with synaptic function and abundantly expressed in TLE patients with very impaired memory performance. In a subsequent promoter analysis, we found the single nucleotide polymorphism rs744373 C-allele to be associated with high mRNA levels of bridging integrator 1 (BIN1)/Amphiphysin 2, i.e. a major component of the endocytotic machinery and located in a crucial genetic AD risk locus. Using in vitro luciferase transfection assays, we found that BIN1 promoter activation is genotype dependent and strongly increased by reduced binding of the transcriptional repressor TGIF. Our data indicate that poor memory performance in patients with TLE strongly corresponds to distinctly altered neuronal transcript signatures, which - as demonstrated for BIN1 - can correlate with a particular allelic promoter variant. Our data suggest aberrant transcriptional signaling to significantly impact synaptic dynamics in TLE resulting in impaired memory performance and may serve as basis for future therapy development of this severe comorbidity.


Assuntos
Epilepsia do Lobo Temporal/genética , Hipocampo/metabolismo , Transtornos da Memória/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Adolescente , Adulto , Criança , Pré-Escolar , Epilepsia do Lobo Temporal/complicações , Feminino , Expressão Gênica , Genótipo , Proteínas de Homeodomínio/genética , Humanos , Lactente , Recém-Nascido , Masculino , Memória/fisiologia , Transtornos da Memória/etiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Proteínas Repressoras/genética , Índice de Gravidade de Doença , Proteínas Supressoras de Tumor/genética , Aprendizagem Verbal/fisiologia , Adulto Jovem
20.
BMC Med Genet ; 17(1): 35, 2016 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-27138190

RESUMO

BACKGROUND: The bladder exstrophy-epispadias complex (BEEC) represents the severe end of the congenital uro-rectal malformation spectrum. Initial studies have implicated rare copy number variations (CNVs), including recurrent duplications of chromosomal region 22q11.21, in BEEC etiology. METHODS: To detect further CNVs, array analysis was performed in 169 BEEC patients. Prior to inclusion, 22q11.21 duplications were excluded using multiplex ligation-dependent probe amplification. RESULTS: Following the application of stringent filter criteria, seven rare CNVs were identified: n = 4, not present in 1307 in-house controls; n = 3, frequency of <0.002 in controls. These CNVs ranged from 1 to 6.08 Mb in size. To identify smaller CNVs, relaxed filter criteria used in the detection of previously reported BEEC associated chromosomal regions were applied. This resulted in the identification of six additional rare CNVs: n = 4, not present in 1307 in-house controls; n = 2, frequency <0.0008 in controls. These CNVs ranged from 0.03-0.08 Mb in size. For 10 of these 13 CNVs, confirmation and segregation analyses were performed (5 of maternal origin; 5 of paternal origin). Interestingly, one female with classic bladder extrophy carried a 1.18 Mb duplication of 22q11.1, a chromosomal region that is associated with cat eye syndrome. CONCLUSIONS: A number of rare CNVs were identified in BEEC patients, and these represent candidates for further evaluation. Rare inherited CNVs may constitute modifiers of, or contributors to, multifactorial BEEC phenotypes.


Assuntos
Extrofia Vesical/genética , Análise Citogenética/métodos , Variações do Número de Cópias de DNA , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Aneuploidia , Transtornos Cromossômicos/genética , Duplicação Cromossômica , Cromossomos Humanos Par 22/genética , Anormalidades do Olho/genética , Feminino , Humanos , Masculino , Herança Materna , Herança Paterna
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