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1.
Nat Commun ; 14(1): 7664, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996417

RESUMO

We present a comprehensive multi-omic analysis of the EPISTOP prospective clinical trial of early intervention with vigabatrin for pre-symptomatic epilepsy treatment in Tuberous Sclerosis Complex (TSC), in which 93 infants with TSC were followed from birth to age 2 years, seeking biomarkers of epilepsy development. Vigabatrin had profound effects on many metabolites, increasing serum deoxycytidine monophosphate (dCMP) levels 52-fold. Most serum proteins and metabolites, and blood RNA species showed significant change with age. Thirty-nine proteins, metabolites, and genes showed significant differences between age-matched control and TSC infants. Six also showed a progressive difference in expression between control, TSC without epilepsy, and TSC with epilepsy groups. A multivariate approach using enrollment samples identified multiple 3-variable predictors of epilepsy, with the best having a positive predictive value of 0.987. This rich dataset will enable further discovery and analysis of developmental effects, and associations with seizure development in TSC.


Assuntos
Epilepsia , Esclerose Tuberosa , Pré-Escolar , Humanos , Lactente , Epilepsia/genética , Multiômica , Estudos Prospectivos , Esclerose Tuberosa/genética , Vigabatrina/uso terapêutico , Recém-Nascido , Ensaios Clínicos como Assunto
2.
Front Plant Sci ; 14: 1277617, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37900765

RESUMO

The action of the petunia strigolactone (SL) hormone receptor DAD2 is dependent not only on its interaction with the PhMAX2A and PhD53A proteins, but also on its expression patterns within the plant. Previously, in a yeast-2-hybrid system, we showed that a series of a single and double amino acid mutants of DAD2 had altered interactions with these binding partners. In this study, we tested the mutants in two plant systems, Arabidopsis and petunia. Testing in Arabidopsis was enabled by creating a CRISPR-Cas9 knockout mutant of the Arabidopsis strigolactone receptor (AtD14). We produced SL receptor activity in both systems using wild type and mutant genes; however, the mutants had functions largely indistinguishable from those of the wild type. The expression of the wild type DAD2 from the CaMV 35S promoter in dad2 petunia produced plants neither quite like the dad2 mutant nor the V26 wild type. These plants had greater height and leaf size although branch number and the plant shape remained more like those of the mutant. These traits may be valuable in the context of a restricted area growing system such as controlled environment agriculture.

3.
bioRxiv ; 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36945593

RESUMO

Cross-regulation between hormone signaling pathways is indispensable for plant growth and development. However, the molecular mechanisms by which multiple hormones interact and co-ordinate activity need to be understood. Here, we generated a cross-regulation network explaining how hormone signals are integrated from multiple pathways in etiolated Arabidopsis (Arabidopsis thaliana) seedlings. To do so we comprehensively characterized transcription factor activity during plant hormone responses and reconstructed dynamic transcriptional regulatory models for six hormones; abscisic acid, brassinosteroid, ethylene, jasmonic acid, salicylic acid and strigolactone/karrikin. These models incorporated target data for hundreds of transcription factors and thousands of protein-protein interactions. Each hormone recruited different combinations of transcription factors, a subset of which were shared between hormones. Hub target genes existed within hormone transcriptional networks, exhibiting transcription factor activity themselves. In addition, a group of MITOGEN-ACTIVATED PROTEIN KINASES (MPKs) were identified as potential key points of cross-regulation between multiple hormones. Accordingly, the loss of function of one of these (MPK6) disrupted the global proteome, phosphoproteome and transcriptome during hormone responses. Lastly, we determined that all hormones drive substantial alternative splicing that has distinct effects on the transcriptome compared with differential gene expression, acting in early hormone responses. These results provide a comprehensive understanding of the common features of plant transcriptional regulatory pathways and how cross-regulation between hormones acts upon gene expression.

4.
Theranostics ; 12(16): 7067-7079, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36276653

RESUMO

The accelerated approval of the monoclonal antibody (mAb) aducanumab as a treatment option for Alzheimer's Disease and the continued discussions about its efficacy have shown that a better understanding of immunotherapy for the treatment of neurodegenerative diseases is needed. 89Zr-immuno-PET could be a suitable tool to open new avenues for the diagnosis of CNS disorders, monitoring disease progression, and assessment of novel therapeutics. Herein, three different 89Zr-labeling strategies and direct radioiodination with 125I of a bispecific anti-amyloid-beta aducanumab derivate, consisting of aducanumab with a C-terminal fused anti-transferrin receptor binding single chain Fab fragment derived from 8D3 (Adu-8D3), were compared ex vivo and in vivo with regard to brain uptake and target engagement in an APP/PS1 Alzheimer's disease mouse model and wild type animals. Methods: Adu-8D3 and a negative control antibody, based on the HIV specific B12 antibody also carrying C-terminal fused 8D3 scFab (B12-8D3), were each conjugated with NCS-DFO, NCS-DFO*, or TFP-N-suc-DFO-Fe-ester, followed by radiolabeling with 89Zr. 125I was used as a substitute for 124I for labeling of both antibodies. 30 µg of radiolabeled mAb, corresponding to approximately 6 MBq 89Zr or 2.5 MBq 125I, were injected per mouse. PET imaging was performed 1, 3 and 7 days post injection (p.i.). All mice were sacrificed on day 7 p.i. and subjected to ex vivo biodistribution and brain autoradiography. Immunostaining on brain tissue was performed after autoradiography for further validation. Results: Ex vivo biodistribution revealed that the brain uptake of [89Zr]Zr-DFO*-NCS-Adu-8D3 (2.19 ±0.12 %ID/g) was as high as for its 125I-analog (2.21 ±0.15 %ID/g). [89Zr]Zr-DFO-NCS-Adu-8D3 and [89Zr]Zr-DFO-N-suc-Adu-8D3 showed significantly lower uptake (< 0.65 %ID/g), being in the same range as for the 89Zr-labeled controls (B12-8D3). Autoradiography of [89Zr]Zr-DFO*-NCS-Adu-8D3 and [125I]I-Adu-8D3 showed an amyloid-beta related granular uptake pattern of radioactivity. In contrast, the [89Zr]Zr-DFO-conjugates and the control antibody groups did not show any amyloid-beta related uptake pattern, indicating that DFO is inferior for 89Zr-immuno-PET imaging of the brain in comparison to DFO* for Adu-8D3. This was confirmed by day 7 PET images showing only amyloid-beta related brain uptake for [89Zr]Zr-DFO*-NCS-Adu-8D3. In wild type animals, such an uptake was not observed. Immunostaining showed a co-localization of all administered Adu-8D3 conjugates with amyloid-beta plaques. Conclusion: We successfully demonstrated that 89Zr-immuno-PET is suitable for imaging and quantifying amyloid-beta specific brain uptake using a bispecific aducanumab brain shuttling antibody, Adu-8D3, but only when using the novel chelator DFO*, and not DFO, for labeling with 89Zr.


Assuntos
Doença de Alzheimer , Anticorpos Biespecíficos , Animais , Camundongos , Radioisótopos do Iodo , Quelantes , Desferroxamina , Zircônio , Distribuição Tecidual , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Linhagem Celular Tumoral , Tomografia por Emissão de Pósitrons/métodos , Anticorpos Monoclonais/uso terapêutico , Peptídeos beta-Amiloides , Fragmentos Fab das Imunoglobulinas , Ésteres
6.
Commun Biol ; 5(1): 338, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35396392

RESUMO

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs) have been identified in bacteria, archaea and mitochondria of plants, but not in eukaryotes. Here, we report the discovery of 12,572 putative CRISPRs randomly distributed across the human chromosomes, which we termed hCRISPRs. By using available transcriptome datasets, we demonstrate that hCRISPRs are distinctively expressed as small non-coding RNAs (sncRNAs) in cell lines and human tissues. Moreover, expression patterns thereof enabled us to distinguish normal from malignant tissues. In prostate cancer, we confirmed the differential hCRISPR expression between normal adjacent and malignant primary prostate tissue by RT-qPCR and demonstrate that the SHERLOCK and DETECTR dipstick tools are suitable to detect these sncRNAs. We anticipate that the discovery of CRISPRs in the human genome can be further exploited for diagnostic purposes in cancer and other medical conditions, which certainly will lead to the development of point-of-care tests based on the differential expression of the hCRISPRs.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Pequeno RNA não Traduzido , Archaea/genética , Bactérias/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Genoma Humano , Humanos , Masculino
7.
Gigascience ; 10(12)2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34891161

RESUMO

BACKGROUND: Fusion genes are typically identified by RNA sequencing (RNA-seq) without elucidating the causal genomic breakpoints. However, non-poly(A)-enriched RNA-seq contains large proportions of intronic reads that also span genomic breakpoints. RESULTS: We have developed an algorithm, Dr. Disco, that searches for fusion transcripts by taking an entire reference genome into account as search space. This includes exons but also introns, intergenic regions, and sequences that do not meet splice junction motifs. Using 1,275 RNA-seq samples, we investigated to what extent genomic breakpoints can be extracted from RNA-seq data and their implications regarding poly(A)-enriched and ribosomal RNA-minus RNA-seq data. Comparison with whole-genome sequencing data revealed that most genomic breakpoints are not, or minimally, transcribed while, in contrast, the genomic breakpoints of all 32 TMPRSS2-ERG-positive tumours were present at RNA level. We also revealed tumours in which the ERG breakpoint was located before ERG, which co-existed with additional deletions and messenger RNA that incorporated intergenic cryptic exons. In breast cancer we identified rearrangement hot spots near CCND1 and in glioma near CDK4 and MDM2 and could directly associate this with increased expression. Furthermore, in all datasets we find fusions to intergenic regions, often spanning multiple cryptic exons that potentially encode neo-antigens. Thus, fusion transcripts other than classical gene-to-gene fusions are prominently present and can be identified using RNA-seq. CONCLUSION: By using the full potential of non-poly(A)-enriched RNA-seq data, sophisticated analysis can reliably identify expressed genomic breakpoints and their transcriptional effects.


Assuntos
Genômica , RNA Ribossômico , Fusão Gênica , Genoma , Análise de Sequência de RNA
8.
Methods Mol Biol ; 2309: 233-243, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34028691

RESUMO

Differential scanning fluorimetry (DSF) is a method used for assessing the interaction of ligands with proteins. In most cases binding of a ligand to proteins tends to increase the melting temperature (Tm) of the protein involved. However, in the case of strigolactone receptors (e.g., D14, AtD14, DAD2, RMS3) from plants, the Tm tends to be reduced in the presence of strigolactones. This is likely due to increased flexibility of the receptors in the presence of hormone ligands.DSF experiments are simple, fast, amenable to high-throughput formats, and cost effective. They have therefore gained in popularity, including within the field of SL signaling. Typically in DSF the receptor protein is purified and incubated with the ligand (strigolactone, agonist, or antagonist) and a (fluorescent) reporter dye. The mixture is then placed in a quantitative PCR instrument and subjected to an increasing temperature gradient. Changes in fluorescence are recorded along the gradient, as the dye interacts with unfolded portions of the protein becoming accessible when the protein "melts". Differences in the temperature at which the protein unfolds in the absence and in the presence of the ligand are interpreted as indicating interactions between the ligand and the receptor.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fluorometria , Compostos Heterocíclicos com 3 Anéis/metabolismo , Lactonas/metabolismo , Receptores de Superfície Celular/metabolismo , Corantes Fluorescentes/metabolismo , Ensaios de Triagem em Larga Escala , Ligantes , Transdução de Sinais
9.
Cancers (Basel) ; 13(9)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33925994

RESUMO

BACKGROUND: Prostate cancer (PCa) is the second most common tumour diagnosed in men. Tumoral heterogeneity in PCa creates a significant challenge to develop robust prognostic markers and novel targets for therapy. An analysis of gene regulatory networks (GRNs) in PCa may provide insight into progressive PCa. Herein, we exploited a graph-based enrichment score to integrate data from GRNs identified in preclinical prostate orthografts and differentially expressed genes in clinical resected PCa. We identified active regulons (transcriptional regulators and their targeted genes) associated with PCa recurrence following radical prostatectomy. METHODS: The expression of known transcription factors and co-factors was analysed in a panel of prostate orthografts (n = 18). We searched for genes (as part of individual GRNs) predicted to be regulated by the highest number of transcriptional factors. Using differentially expressed gene analysis (on a per sample basis) coupled with gene graph enrichment analysis, we identified candidate genes and associated GRNs in PCa within the UTA cohort, with the most enriched regulon being JMJD6, which was further validated in two additional cohorts, namely EMC and ICGC cohorts. Cox regression analysis was performed to evaluate the association of the JMJD6 regulon activity with disease-free survival time in the three clinical cohorts as well as compared to three published prognostic gene signatures (TMCC11, BROMO-10 and HYPOXIA-28). RESULTS: 1308 regulons were correlated to transcriptomic data from the three clinical prostatectomy cohorts. The JMJD6 regulon was identified as the top enriched regulon in the UTA cohort and again validated in the EMC cohort as the top-ranking regulon. In both UTA and EMC cohorts, the JMJD6 regulon was significantly associated with cancer recurrence. Active JMJD6 regulon also correlated with disease recurrence in the ICGC cohort. Furthermore, Kaplan-Meier analysis confirmed shorter time to recurrence in patients with active JMJD6 regulon for all three clinical cohorts (UTA, EMC and ICGC), which was not the case for three published prognostic gene signatures (TMCC11, BROMO-10 and HYPOXIA-28). In multivariate analysis, the JMJD6 regulon status significantly predicted disease recurrence in the UTA and EMC, but not ICGC datasets, while none of the three published signatures significantly prognosticate for cancer recurrence. CONCLUSIONS: We have characterised gene regulatory networks from preclinical prostate orthografts and applied transcriptomic data from three clinical cohorts to evaluate the prognostic potential of the JMJD6 regulon.

10.
Plant Physiol ; 187(3): 1033-1044, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33616657

RESUMO

The architecture of flowering plants exhibits both phenotypic diversity and plasticity, determined, in part, by the number and activity of axillary meristems and, in part, by the growth characteristics of the branches that develop from the axillary buds. The plasticity of shoot branching results from a combination of various intrinsic and genetic elements, such as number and position of nodes and type of growth phase, as well as environmental signals such as nutrient availability, light characteristics, and temperature (Napoli et al., 1998; Bennett and Leyser, 2006; Janssen et al., 2014; Teichmann and Muhr, 2015; Ueda and Yanagisawa, 2019). Axillary meristem initiation and axillary bud outgrowth are controlled by a complex and interconnected regulatory network. Although many of the genes and hormones that modulate branching patterns have been discovered and characterized through genetic and biochemical studies, there are still many gaps in our understanding of the control mechanisms at play. In this review, we will summarize our current knowledge of the control of axillary meristem initiation and outgrowth into a branch.


Assuntos
Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Magnoliopsida/genética , Reguladores de Crescimento de Plantas/metabolismo , Plasticidade Celular , Magnoliopsida/crescimento & desenvolvimento , Meristema/genética , Meristema/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento
11.
Leukemia ; 35(1): 47-61, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32127641

RESUMO

Acute myeloid leukemia (AML) is caused by genetic aberrations that also govern the prognosis of patients and guide risk-adapted and targeted therapy. Genetic aberrations in AML are structurally diverse and currently detected by different diagnostic assays. This study sought to establish whole transcriptome RNA sequencing as single, comprehensive, and flexible platform for AML diagnostics. We developed HAMLET (Human AML Expedited Transcriptomics) as bioinformatics pipeline for simultaneous detection of fusion genes, small variants, tandem duplications, and gene expression with all information assembled in an annotated, user-friendly output file. Whole transcriptome RNA sequencing was performed on 100 AML cases and HAMLET results were validated by reference assays and targeted resequencing. The data showed that HAMLET accurately detected all fusion genes and overexpression of EVI1 irrespective of 3q26 aberrations. In addition, small variants in 13 genes that are often mutated in AML were called with 99.2% sensitivity and 100% specificity, and tandem duplications in FLT3 and KMT2A were detected by a novel algorithm based on soft-clipped reads with 100% sensitivity and 97.1% specificity. In conclusion, HAMLET has the potential to provide accurate comprehensive diagnostic information relevant for AML classification, risk assessment and targeted therapy on a single technology platform.


Assuntos
Sequenciamento do Exoma , Perfilação da Expressão Gênica , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Transcriptoma , Biomarcadores Tumorais , Biologia Computacional/métodos , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Leucêmica da Expressão Gênica , Variação Genética , Genômica/métodos , Humanos , Masculino , Técnicas de Diagnóstico Molecular , Mutação , Proteínas de Fusão Oncogênica , Prognóstico , Reprodutibilidade dos Testes , Sequenciamento do Exoma/métodos
12.
IUCrJ ; 7(Pt 5): 860-869, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32939278

RESUMO

Direct detector device (DDD) cameras have revolutionized electron cryomicroscopy (cryoEM) with their high detective quantum efficiency (DQE) and output of movie data. A high ratio of camera frame rate (frames per second) to camera exposure rate (electrons per pixel per second) allows electron counting, which further improves the DQE and enables the recording of super-resolution information. Movie output also allows the correction of specimen movement and compensation for radiation damage. However, these movies come at the cost of producing large volumes of data. It is common practice to sum groups of successive camera frames to reduce the final frame rate, and therefore the file size, to one suitable for storage and image processing. This reduction in the temporal resolution of the camera requires decisions to be made during data acquisition that may result in the loss of information that could have been advantageous during image analysis. Here, experimental analysis of a new electron-event representation (EER) data format for electron-counting DDD movies is presented, which is enabled by new hardware developed by Thermo Fisher Scientific for their Falcon DDD cameras. This format enables the recording of DDD movies at the raw camera frame rate without sacrificing either spatial or temporal resolution. Experimental data demonstrate that the method retains super-resolution information and allows the correction of specimen movement at the physical frame rate of the camera while maintaining manageable file sizes. The EER format will enable the development of new methods that can utilize the full spatial and temporal resolution of DDD cameras.

13.
J Biol Chem ; 295(13): 4181-4193, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32071083

RESUMO

Strigolactones (SLs) are terpenoid-derived plant hormones that regulate various developmental processes, particularly shoot branching, root development, and leaf senescence. The SL receptor has an unusual mode of action. Upon binding SL, it hydrolyzes the hormone, and then covalently binds one of the hydrolytic products. These initial events enable the SL receptor DAD2 (in petunia) to interact with the F-box protein PhMAX2A of the Skp-Cullin-F-box (SCF) complex and/or a repressor of SL signaling, PhD53A. However, it remains unclear how binding and hydrolysis structurally alters the SL receptor to enable its engagement with signaling partners. Here, we used mutagenesis to alter DAD2 and affect SL hydrolysis or DAD2's ability to interact with its signaling partners. We identified three DAD2 variants whose hydrolytic activity had been separated from the receptor's interactions with PhMAX2A or PhD53A. Two variants, DAD2N242I and DAD2F135A, having substitutions in the core α/ß hydrolase-fold domain and the hairpin, exhibited hormone-independent interactions with PhMAX2A and PhD53A, respectively. Conversely, the DAD2D166A variant could not interact with PhMAX2A in the presence of SL, but its interaction with PhD53A remained unaffected. Structural analyses of DAD2N242I and DAD2D166A revealed only small differences compared with the structure of the WT receptor. Results of molecular dynamics simulations of the DAD2N242I structure suggested that increased flexibility is a likely cause for its SL-independent interaction with PhMAX2A. Our results suggest that PhMAX2A and PhD53A have distinct binding sites on the SL receptor and that its flexibility is a major determinant of its interactions with these two downstream regulators.


Assuntos
Compostos Heterocíclicos com 3 Anéis/química , Lactonas/química , Petunia/química , Reguladores de Crescimento de Plantas/genética , Proteínas de Plantas/química , Proteínas F-Box/química , Proteínas F-Box/genética , Regulação da Expressão Gênica de Plantas/genética , Hidrolases/química , Hidrolases/genética , Petunia/genética , Reguladores de Crescimento de Plantas/química , Proteínas de Plantas/genética , Ligação Proteica/genética , Proteínas Ligases SKP Culina F-Box/química , Proteínas Ligases SKP Culina F-Box/genética , Transdução de Sinais/genética
14.
Genes Chromosomes Cancer ; 59(6): 366-374, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32017278

RESUMO

Melanoma demonstrates altered patterns of DNA methylation that are associated with genetic instability and transcriptional repression of numerous genes. Active DNA demethylation is mediated by TET enzymes that catalyze conversion of 5-methylcytosine (mC) to 5-hydroxymethylcytosine (hmC). Loss of hmC occurs in melanoma and correlates with disease progression. Here we analyzed the genomic distribution of hmC along with mC in nevus and melanoma using oxidative bisulfite chemistry combined with high-density arrays. HmC was enriched relative to mC at enhancers, 5'UTR regions and CpG shores in nevus and melanoma samples, pointing to specific TET enzyme activity. The proportion of interrogated CpG sites with high hmC levels was lower in melanoma (0.54%) than in nevus (2.0%). Depletion of hmC in melanoma was evident across all chromosomes and intragenic regions, being more pronounced in metastatic than in non-metastatic tumors. The patterns of hmC distribution in melanoma samples differed significantly from those in nevus samples, exceeding differences in mC patterns. We identified specific CpG sites and regions with significantly lower hmC levels in melanoma than in nevus that might serve as diagnostic markers. Differentially hydroxymethylated regions localized to cancer-related genes, including the PTEN gene promoter, suggesting that deregulated DNA hydroxymethylation may contribute to melanoma pathogenesis.


Assuntos
5-Metilcitosina/análogos & derivados , Biomarcadores Tumorais/genética , Metilação de DNA , Melanoma/genética , Nevo/genética , Regiões 5' não Traduzidas , 5-Metilcitosina/análise , Adulto , Ilhas de CpG , Feminino , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Nevo/patologia
15.
J Biol Chem ; 293(17): 6530-6543, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29523686

RESUMO

The strigolactone (SL) family of plant hormones regulates a broad range of physiological processes affecting plant growth and development and also plays essential roles in controlling interactions with parasitic weeds and symbiotic fungi. Recent progress elucidating details of SL biosynthesis, signaling, and transport offers many opportunities for discovering new plant-growth regulators via chemical interference. Here, using high-throughput screening and downstream biochemical assays, we identified N-phenylanthranilic acid derivatives as potent inhibitors of the SL receptors from petunia (DAD2), rice (OsD14), and Arabidopsis (AtD14). Crystal structures of DAD2 and OsD14 in complex with inhibitors further provided detailed insights into the inhibition mechanism, and in silico modeling of 19 other plant strigolactone receptors suggested that these compounds are active across a large range of plant species. Altogether, these results provide chemical tools for investigating SL signaling and further define a framework for structure-based approaches to design and validate optimized inhibitors of SL receptors for specific plant targets.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Modelos Moleculares , Oryza , Petunia , Receptores de Superfície Celular , ortoaminobenzoatos , Arabidopsis/química , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/antagonistas & inibidores , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Simulação por Computador , Oryza/química , Oryza/genética , Oryza/metabolismo , Petunia/química , Petunia/genética , Petunia/metabolismo , Receptores de Superfície Celular/antagonistas & inibidores , Receptores de Superfície Celular/química , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Relação Estrutura-Atividade , ortoaminobenzoatos/química , ortoaminobenzoatos/farmacologia
16.
J Exp Bot ; 69(9): 2379-2390, 2018 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-29190381

RESUMO

Branching has a major influence on the overall shape and productivity of a plant. Strigolactones (SLs) have been identified as plant hormones that have a key role in suppressing the outgrowth of axillary meristems. CAROTENOID CLEAVAGE DIOXYGENASE (CCD) genes are integral to the biosynthesis of SLs and are well characterized in annual plants, but their role in woody perennials is relatively unknown. We identified CCD7 and CCD8 orthologues from apple and demonstrated that MdCCD7 and MdCCD8 are able to complement the Arabidopsis branching mutants max3 and max4 respectively, indicating conserved function. RNAi lines of MdCCD7 show reduced gene expression and increased branching in apple. We performed reciprocal grafting experiments with combinations of MdCCD7 RNAi and wild-type 'Royal Gala' as rootstocks and scion. Unexpectedly, wild-type roots were unable to suppress branching in MdCCD7 RNAi scions. Another key finding was that MdCCD7 RNAi scions initiated phytomers at an increased rate relative to the wild type, resulting in a greater node number and primary shoot length. We suggest that localized SL biosynthesis in the shoot, rather than roots, controls axillary bud outgrowth and shoot growth rate in apple.


Assuntos
Dioxigenases/genética , Lactonas/metabolismo , Malus/genética , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Brotos de Planta/crescimento & desenvolvimento , Dioxigenases/metabolismo , Regulação da Expressão Gênica de Plantas , Malus/crescimento & desenvolvimento , Malus/metabolismo , Proteínas de Plantas/metabolismo , Brotos de Planta/genética
17.
Sci Rep ; 7(1): 8089, 2017 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-28808237

RESUMO

Tuberous Sclerosis Complex (TSC) is a rare genetic disorder that results from a mutation in the TSC1 or TSC2 genes leading to constitutive activation of the mechanistic target of rapamycin complex 1 (mTORC1). TSC is associated with autism, intellectual disability and severe epilepsy. Cortical tubers are believed to represent the neuropathological substrates of these disabling manifestations in TSC. In the presented study we used high-throughput RNA sequencing in combination with systems-based computational approaches to investigate the complexity of the TSC molecular network. Overall we detected 438 differentially expressed genes and 991 differentially expressed small non-coding RNAs in cortical tubers compared to autopsy control brain tissue. We observed increased expression of genes associated with inflammatory, innate and adaptive immune responses. In contrast, we observed a down-regulation of genes associated with neurogenesis and glutamate receptor signaling. MicroRNAs represented the largest class of over-expressed small non-coding RNA species in tubers. In particular, our analysis revealed that the miR-34 family (including miR-34a, miR-34b and miR-34c) was significantly over-expressed. Functional studies demonstrated the ability of miR-34b to modulate neurite outgrowth in mouse primary hippocampal neuronal cultures. This study provides new insights into the TSC transcriptomic network along with the identification of potential new treatment targets.


Assuntos
Transcrição Gênica/genética , Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética , Esclerose Tuberosa/genética , Adolescente , Adulto , Animais , Córtex Cerebral/fisiologia , Criança , Pré-Escolar , Epilepsia/genética , Feminino , Humanos , Lactente , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Pessoa de Meia-Idade , Mutação/genética , Neurônios/fisiologia , Transdução de Sinais/genética , Adulto Jovem
18.
Hum Mutat ; 38(8): 912-921, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28471515

RESUMO

Next-generation sequencing is radically changing how DNA diagnostic laboratories operate. What started as a single-gene profession is now developing into gene panel sequencing and whole-exome and whole-genome sequencing (WES/WGS) analyses. With further advances in sequencing technology and concomitant price reductions, WGS will soon become the standard and be routinely offered. Here, we focus on the critical steps involved in performing WGS, with a particular emphasis on points where WGS differs from WES, the important variables that should be taken into account, and the quality control measures that can be taken to monitor the process. The points discussed here, combined with recent publications on guidelines for reporting variants, will facilitate the routine implementation of WGS into a diagnostic setting.


Assuntos
Genoma Humano/genética , Exoma/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Proteína 2 de Ligação a Metil-CpG/genética , Polimorfismo de Nucleotídeo Único/genética
19.
Stem Cell Reports ; 8(5): 1340-1353, 2017 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-28494940

RESUMO

The ability to form teratomas in vivo containing multiple somatic cell types is regarded as functional evidence of pluripotency for human pluripotent stem cells (hPSCs). Since the Teratoma assay is animal dependent, laborious, and only qualitative, the PluriTest and the hPSC ScoreCard assay have been developed as in vitro alternatives. Here we compared normal hPSCs, induced hPSCs (hiPSCs) with reactivated reprogramming transgenes, and human embryonal carcinoma cells (hECs) in these assays. While normal hPSCs gave rise to typical teratomas, the xenografts of the hECs and the hiPSCs with reactivated reprogramming transgenes were largely undifferentiated and malignant. The hPSC ScoreCard assay confirmed the line-specific differentiation propensities in vitro. However, when undifferentiated cells were analyzed by the PluriTest, only hECs were identified as abnormal whereas all other cell lines were indistinguishable and resembled normal hPSCs. Our results indicate that pluripotency assays are best selected on the basis of intended downstream applications.


Assuntos
Testes de Carcinogenicidade/normas , Diferenciação Celular , Células-Tronco Pluripotentes Induzidas/citologia , Teratoma/patologia , Ensaios Antitumorais Modelo de Xenoenxerto/normas , Animais , Testes de Carcinogenicidade/efeitos adversos , Testes de Carcinogenicidade/métodos , Linhagem Celular , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
20.
Hum Mutat ; 38(7): 870-879, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28378423

RESUMO

A genetic diagnosis of autosomal-dominant polycystic kidney disease (ADPKD) is challenging due to allelic heterogeneity, high GC content, and homology of the PKD1 gene with six pseudogenes. Short-read next-generation sequencing approaches, such as whole-genome sequencing and whole-exome sequencing, often fail at reliably characterizing complex regions such as PKD1. However, long-read single-molecule sequencing has been shown to be an alternative strategy that could overcome PKD1 complexities and discriminate between homologous regions of PKD1 and its pseudogenes. In this study, we present the increased power of resolution for complex regions using long-read sequencing to characterize a cohort of 19 patients with ADPKD. Our approach provided high sensitivity in identifying PKD1 pathogenic variants, diagnosing 94.7% of the patients. We show that reliable screening of ADPKD patients in a single test without interference of PKD1 homologous sequences, commonly introduced by residual amplification of PKD1 pseudogenes, by direct long-read sequencing is now possible. This strategy can be implemented in diagnostics and is highly suitable to sequence and resolve complex genomic regions that are of clinical relevance.


Assuntos
Doenças Renais Policísticas/genética , Canais de Cátion TRPP/genética , Alelos , Estudos de Coortes , Biblioteca Gênica , Testes Genéticos , Genótipo , Humanos , Perda de Heterozigosidade , Rim Policístico Autossômico Dominante/genética , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Pseudogenes , Análise de Sequência de DNA
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