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1.
F1000Res ; 13: 8, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38779317

RESUMO

Biomedical research projects are becoming increasingly complex and require technological solutions that support all phases of the data lifecycle and application of the FAIR principles. At the Berlin Institute of Health (BIH), we have developed and established a flexible and cost-effective approach to building customized cloud platforms for supporting research projects. The approach is based on a microservice architecture and on the management of a portfolio of supported services. On this basis, we created and maintained cloud platforms for several international research projects. In this article, we present our approach and argue that building customized cloud platforms can offer multiple advantages over using multi-project platforms. Our approach is transferable to other research environments and can be easily adapted by other projects and other service providers.


Assuntos
Pesquisa Biomédica , Computação em Nuvem , Gerenciamento de Dados , Humanos , Gerenciamento de Dados/métodos
2.
JAMA Psychiatry ; 80(10): 1066-1074, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37610741

RESUMO

Importance: Climate change, pollution, urbanization, socioeconomic inequality, and psychosocial effects of the COVID-19 pandemic have caused massive changes in environmental conditions that affect brain health during the life span, both on a population level as well as on the level of the individual. How these environmental factors influence the brain, behavior, and mental illness is not well known. Observations: A research strategy enabling population neuroscience to contribute to identify brain mechanisms underlying environment-related mental illness by leveraging innovative enrichment tools for data federation, geospatial observation, climate and pollution measures, digital health, and novel data integration techniques is described. This strategy can inform innovative treatments that target causal cognitive and molecular mechanisms of mental illness related to the environment. An example is presented of the environMENTAL Project that is leveraging federated cohort data of over 1.5 million European citizens and patients enriched with deep phenotyping data from large-scale behavioral neuroimaging cohorts to identify brain mechanisms related to environmental adversity underlying symptoms of depression, anxiety, stress, and substance misuse. Conclusions and Relevance: This research will lead to the development of objective biomarkers and evidence-based interventions that will significantly improve outcomes of environment-related mental illness.


Assuntos
COVID-19 , Saúde Mental , Humanos , COVID-19/epidemiologia , Pandemias , Transtornos de Ansiedade , Ansiedade
3.
F1000Res ; 10: 33, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34035898

RESUMO

Data analysis often entails a multitude of heterogeneous steps, from the application of various command line tools to the usage of scripting languages like R or Python for the generation of plots and tables. It is widely recognized that data analyses should ideally be conducted in a reproducible way. Reproducibility enables technical validation and regeneration of results on the original or even new data. However, reproducibility alone is by no means sufficient to deliver an analysis that is of lasting impact (i.e., sustainable) for the field, or even just one research group. We postulate that it is equally important to ensure adaptability and transparency. The former describes the ability to modify the analysis to answer extended or slightly different research questions. The latter describes the ability to understand the analysis in order to judge whether it is not only technically, but methodologically valid. Here, we analyze the properties needed for a data analysis to become reproducible, adaptable, and transparent. We show how the popular workflow management system Snakemake can be used to guarantee this, and how it enables an ergonomic, combined, unified representation of all steps involved in data analysis, ranging from raw data processing, to quality control and fine-grained, interactive exploration and plotting of final results.


Assuntos
Análise de Dados , Software , Reprodutibilidade dos Testes , Fluxo de Trabalho
5.
Nat Med ; 27(4): 616-619, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33619368

RESUMO

B cell maturation antigen (BCMA) is a target for various immunotherapies and a biomarker for tumor load in multiple myeloma (MM). We report a case of irreversible BCMA loss in a patient with MM who was enrolled in the KarMMa trial ( NCT03361748 ) and progressed after anti-BCMA CAR T cell therapy. We identified selection of a clone with homozygous deletion of TNFRSF17 (BCMA) as the underlying mechanism of immune escape. Furthermore, we found heterozygous TNFRSF17 loss or monosomy 16 in 37 out of 168 patients with MM, including 28 out of 33 patients with hyperhaploid MM who had not been previously treated with BCMA-targeting therapies, suggesting that heterozygous TNFRSF17 deletion at baseline could theoretically be a risk factor for BCMA loss after immunotherapy.


Assuntos
Antígeno de Maturação de Linfócitos B/genética , Deleção de Genes , Mieloma Múltiplo/genética , Mieloma Múltiplo/imunologia , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/imunologia , Idoso , Antígenos de Neoplasias/metabolismo , Variações do Número de Cópias de DNA/genética , Homozigoto , Humanos , Imageamento por Ressonância Magnética , Masculino , Mieloma Múltiplo/diagnóstico por imagem
6.
Brief Bioinform ; 22(5)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33589928

RESUMO

This article describes some use case studies and self-assessments of FAIR status of de.NBI services to illustrate the challenges and requirements for the definition of the needs of adhering to the FAIR (findable, accessible, interoperable and reusable) data principles in a large distributed bioinformatics infrastructure. We address the challenge of heterogeneity of wet lab technologies, data, metadata, software, computational workflows and the levels of implementation and monitoring of FAIR principles within the different bioinformatics sub-disciplines joint in de.NBI. On the one hand, this broad service landscape and the excellent network of experts are a strong basis for the development of useful research data management plans. On the other hand, the large number of tools and techniques maintained by distributed teams renders FAIR compliance challenging.


Assuntos
Gerenciamento de Dados/métodos , Metadados , Redes Neurais de Computação , Proteômica/métodos , Software , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Cooperação Internacional , Fenótipo , Plantas/genética , Proteoma , Autoavaliação (Psicologia) , Fluxo de Trabalho
7.
Nat Biotechnol ; 39(6): 705-716, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33361824

RESUMO

In coronavirus disease 2019 (COVID-19), hypertension and cardiovascular diseases are major risk factors for critical disease progression. However, the underlying causes and the effects of the main anti-hypertensive therapies-angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs)-remain unclear. Combining clinical data (n = 144) and single-cell sequencing data of airway samples (n = 48) with in vitro experiments, we observed a distinct inflammatory predisposition of immune cells in patients with hypertension that correlated with critical COVID-19 progression. ACEI treatment was associated with dampened COVID-19-related hyperinflammation and with increased cell intrinsic antiviral responses, whereas ARB treatment related to enhanced epithelial-immune cell interactions. Macrophages and neutrophils of patients with hypertension, in particular under ARB treatment, exhibited higher expression of the pro-inflammatory cytokines CCL3 and CCL4 and the chemokine receptor CCR1. Although the limited size of our cohort does not allow us to establish clinical efficacy, our data suggest that the clinical benefits of ACEI treatment in patients with COVID-19 who have hypertension warrant further investigation.


Assuntos
Tratamento Farmacológico da COVID-19 , Quimiocina CCL3/genética , Quimiocina CCL4/genética , Hipertensão/tratamento farmacológico , Receptores CCR1/genética , Adulto , Antagonistas de Receptores de Angiotensina/administração & dosagem , Antagonistas de Receptores de Angiotensina/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , COVID-19/complicações , COVID-19/genética , COVID-19/virologia , Progressão da Doença , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hipertensão/complicações , Hipertensão/genética , Hipertensão/patologia , Inflamação/complicações , Inflamação/tratamento farmacológico , Inflamação/genética , Inflamação/virologia , Masculino , Pessoa de Meia-Idade , RNA-Seq , Sistema Respiratório/efeitos dos fármacos , Sistema Respiratório/patologia , Sistema Respiratório/virologia , Fatores de Risco , SARS-CoV-2/patogenicidade , Análise de Célula Única
8.
Leukemia ; 35(4): 1108-1120, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32753690

RESUMO

Myeloid neoplasms are characterized by frequent mutations in at least seven components of the spliceosome that have distinct roles in the process of pre-mRNA splicing. Hotspot mutations in SF3B1, SRSF2, U2AF1 and loss of function mutations in ZRSR2 have revealed widely different aberrant splicing signatures with little overlap. However, previous studies lacked the power necessary to identify commonly mis-spliced transcripts in heterogeneous patient cohorts. By performing RNA-Seq on bone marrow samples from 1258 myeloid neoplasm patients and 63 healthy bone marrow donors, we identified transcripts frequently mis-spliced by mutated splicing factors (SF), rare SF mutations with common alternative splicing (AS) signatures, and SF-dependent neojunctions. We characterized 17,300 dysregulated AS events using a pipeline designed to predict the impact of mis-splicing on protein function. Meta-splicing analysis revealed a pattern of reduced levels of retained introns among disease samples that was exacerbated in patients with splicing factor mutations. These introns share characteristics with "detained introns," a class of introns that have been shown to promote differentiation by detaining pro-proliferative transcripts in the nucleus. In this study, we have functionally characterized 17,300 targets of mis-splicing by the SF mutations, identifying a common pathway by which AS may promote maintenance of a proliferative state.


Assuntos
Processamento Alternativo , Biomarcadores Tumorais , Regulação Neoplásica da Expressão Gênica , Transtornos Mieloproliferativos/genética , Medula Óssea/patologia , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Estudos de Casos e Controles , Deleção Cromossômica , Análise por Conglomerados , Suscetibilidade a Doenças , Perfilação da Expressão Gênica , Humanos , Mutação com Perda de Função , Mutação , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/terapia , Transtornos Mieloproliferativos/diagnóstico , Transtornos Mieloproliferativos/terapia , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Transcriptoma
9.
Nat Biotechnol ; 38(8): 970-979, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32591762

RESUMO

To investigate the immune response and mechanisms associated with severe coronavirus disease 2019 (COVID-19), we performed single-cell RNA sequencing on nasopharyngeal and bronchial samples from 19 clinically well-characterized patients with moderate or critical disease and from five healthy controls. We identified airway epithelial cell types and states vulnerable to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In patients with COVID-19, epithelial cells showed an average three-fold increase in expression of the SARS-CoV-2 entry receptor ACE2, which correlated with interferon signals by immune cells. Compared to moderate cases, critical cases exhibited stronger interactions between epithelial and immune cells, as indicated by ligand-receptor expression profiles, and activated immune cells, including inflammatory macrophages expressing CCL2, CCL3, CCL20, CXCL1, CXCL3, CXCL10, IL8, IL1B and TNF. The transcriptional differences in critical cases compared to moderate cases likely contribute to clinical observations of heightened inflammatory tissue damage, lung injury and respiratory failure. Our data suggest that pharmacologic inhibition of the CCR1 and/or CCR5 pathways might suppress immune hyperactivation in critical COVID-19.


Assuntos
Infecções por Coronavirus/patologia , Infecções por Coronavirus/fisiopatologia , Pneumonia Viral/patologia , Pneumonia Viral/fisiopatologia , Sistema Respiratório/patologia , Análise de Célula Única , Transcriptoma , Adulto , Idoso , Enzima de Conversão de Angiotensina 2 , Líquido da Lavagem Broncoalveolar/virologia , COVID-19 , Comunicação Celular , Diferenciação Celular , Infecções por Coronavirus/virologia , Células Epiteliais/patologia , Células Epiteliais/virologia , Feminino , Humanos , Sistema Imunitário/patologia , Inflamação/imunologia , Inflamação/patologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Pandemias , Peptidil Dipeptidase A/genética , Pneumonia Viral/virologia , Sistema Respiratório/imunologia , Sistema Respiratório/virologia , Índice de Gravidade de Doença
10.
Blood ; 136(16): 1851-1862, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32573691

RESUMO

More than 90% of patients with myelodysplastic/myeloproliferative neoplasms (MDSs/MPNs) harbor somatic mutations in myeloid-related genes, but still, current diagnostic criteria do not include molecular data. We performed genome-wide sequencing techniques to characterize the mutational landscape of a large and clinically well-characterized cohort including 367 adults with MDS/MPN subtypes, including chronic myelomonocytic leukemia (CMML; n = 119), atypical chronic myeloid leukemia (aCML; n = 71), MDS/MPN with ring sideroblasts and thrombocytosis (MDS/MPN-RS-T; n = 71), and MDS/MPN unclassifiable (MDS/MPN-U; n = 106). A total of 30 genes were recurrently mutated in ≥3% of the cohort. Distribution of recurrently mutated genes and clonal architecture differed among MDS/MPN subtypes. Statistical analysis revealed significant correlations between recurrently mutated genes, as well as genotype-phenotype associations. We identified specific gene combinations that were associated with distinct MDS/MPN subtypes and that were mutually exclusive with most of the other MDSs/MPNs (eg, TET2-SRSF2 in CMML, ASXL1-SETBP1 in aCML, and SF3B1-JAK2 in MDS/MPN-RS-T). Patients with MDS/MPN-U were the most heterogeneous and displayed different molecular profiles that mimicked the ones observed in other MDS/MPN subtypes and that had an impact on the outcome of the patients. Specific gene mutations also had an impact on the outcome of the different MDS/MPN subtypes, which may be relevant for clinical decision-making. Overall, the results of this study help to elucidate the heterogeneity found in these neoplasms, which can be of use in the clinical setting of MDS/MPN.


Assuntos
Evolução Clonal , Hematopoiese Clonal , Suscetibilidade a Doenças , Doenças Mieloproliferativas-Mielodisplásicas/etiologia , Idoso , Idoso de 80 Anos ou mais , Alelos , Biomarcadores , Medula Óssea , Aberrações Cromossômicas , Evolução Clonal/genética , Hematopoiese Clonal/genética , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Doenças Mieloproliferativas-Mielodisplásicas/diagnóstico , Doenças Mieloproliferativas-Mielodisplásicas/metabolismo , Doenças Mieloproliferativas-Mielodisplásicas/mortalidade , Fenótipo , Prognóstico , Sequenciamento do Exoma , Sequenciamento Completo do Genoma
11.
Cancer Genet ; 242: 15-24, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31980417

RESUMO

The diagnosis and risk stratification of multiple myeloma (MM) is based on clinical and cytogenetic tests. Magnetic CD138 enrichment followed by interphase FISH (fluorescence in situ hybridisation) is the gold standard to identify prognostic translocations and copy number alterations (CNA). Although clinical implications of gene expression profiling (GEP) or panel based sequencing results are evident, those tests have not yet reached routine clinical application. We set up a single workflow to analyse MM of 211 patients at first diagnosis by whole genome sequencing (WGS) and RNA-Seq and validate the results by FISH analysis. We observed a 96% concordance of FISH and WGS results when assessing translocations involving the IGH locus and an overall concordance of FISH and WGS of 92% when assessing CNA. WGS analysis resulted in the identification of 17 additional MYC-translocations that were missed by FISH analysis. RNA-Seq followed by supervised clustering grouped patients in their expected genetically defined subgroup and prompted the assessment of WGS data in cases that were not congruent with FISH. This allowed the identification of additional IGH-translocations and hyperdiploid cases. We show the reliability of WGS an RNA-Seq in a clinical setting, which is a prerequisite for a novel routine diagnostic test.


Assuntos
Mieloma Múltiplo/diagnóstico , RNA-Seq , Sequenciamento Completo do Genoma , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Medula Óssea/patologia , Variações do Número de Cópias de DNA , Testes Diagnósticos de Rotina , Feminino , Perfilação da Expressão Gênica , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Medição de Risco , Deleção de Sequência , Sindecana-1/genética , Translocação Genética
12.
PLoS Comput Biol ; 15(8): e1007332, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31469830

RESUMO

The confluence of deep sequencing and powerful machine learning is providing an unprecedented peek at the darkest of the dark genomic matter, the non-coding genomic regions lacking any functional annotation. While deep sequencing uncovers rare tumor variants, the heterogeneity of the disease confounds the best of machine learning (ML) algorithms. Here we set out to answer if the dark-matter of the genome encompass signals that can distinguish the fine subtypes of disease that are otherwise genomically indistinguishable. We introduce a novel stochastic regularization, ReVeaL, that empowers ML to discriminate subtle cancer subtypes even from the same 'cell of origin'. Analogous to heritability, implicitly defined on whole genome, we use predictability (F1 score) definable on portions of the genome. In an effort to distinguish cancer subtypes using dark-matter DNA, we applied ReVeaL to a new WGS dataset from 727 patient samples with seven forms of hematological cancers and assessed the predictivity over several genomic regions including genic, non-dark, non-coding, non-genic, and dark. ReVeaL enabled improved discrimination of cancer subtypes for all segments of the genome. The non-genic, non-coding and dark-matter had the highest F1 scores, with dark-matter having the highest level of predictability. Based on ReVeaL's predictability of different genomic regions, dark-matter contains enough signal to significantly discriminate fine subtypes of disease. Hence, the agglomeration of rare variants, even in the hitherto unannotated and ill-understood regions of the genome, may play a substantial role in the disease etiology and deserve much more attention.


Assuntos
Algoritmos , DNA de Neoplasias/genética , Neoplasias Hematológicas/classificação , Neoplasias Hematológicas/genética , Modelos Genéticos , Biologia Computacional , Bases de Dados de Ácidos Nucleicos , Frequência do Gene , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Aprendizado de Máquina , Polimorfismo de Nucleotídeo Único , RNA não Traduzido/genética , Processos Estocásticos , Sequenciamento Completo do Genoma
14.
Nat Genet ; 51(5): 885-895, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30962619

RESUMO

The domestication of wild emmer wheat led to the selection of modern durum wheat, grown mainly for pasta production. We describe the 10.45 gigabase (Gb) assembly of the genome of durum wheat cultivar Svevo. The assembly enabled genome-wide genetic diversity analyses revealing the changes imposed by thousands of years of empirical selection and breeding. Regions exhibiting strong signatures of genetic divergence associated with domestication and breeding were widespread in the genome with several major diversity losses in the pericentromeric regions. A locus on chromosome 5B carries a gene encoding a metal transporter (TdHMA3-B1) with a non-functional variant causing high accumulation of cadmium in grain. The high-cadmium allele, widespread among durum cultivars but undetected in wild emmer accessions, increased in frequency from domesticated emmer to modern durum wheat. The rapid cloning of TdHMA3-B1 rescues a wild beneficial allele and demonstrates the practical use of the Svevo genome for wheat improvement.


Assuntos
Triticum/genética , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Cádmio/metabolismo , Cromossomos de Plantas/genética , Domesticação , Variação Genética , Genoma de Planta , Filogenia , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Seleção Genética , Sintenia , Tetraploidia , Triticum/classificação , Triticum/metabolismo
15.
Genome Biol ; 19(1): 104, 2018 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-30115097

RESUMO

BACKGROUND: Recent improvements in DNA sequencing and genome scaffolding have paved the way to generate high-quality de novo assemblies of pseudomolecules representing complete chromosomes of wheat and its wild relatives. These assemblies form the basis to compare the dynamics of wheat genomes on a megabase scale. RESULTS: Here, we provide a comparative sequence analysis of the 700-megabase chromosome 2D between two bread wheat genotypes-the old landrace Chinese Spring and the elite Swiss spring wheat line 'CH Campala Lr22a'. Both chromosomes were assembled into megabase-sized scaffolds. There is a high degree of sequence conservation between the two chromosomes. Analysis of large structural variations reveals four large indels of more than 100 kb. Based on the molecular signatures at the breakpoints, unequal crossing over and double-strand break repair were identified as the molecular mechanisms that caused these indels. Three of the large indels affect copy number of NLRs, a gene family involved in plant immunity. Analysis of SNP density reveals four haploblocks of 4, 8, 9 and 48 Mb with a 35-fold increased SNP density compared to the rest of the chromosome. Gene content across the two chromosomes was highly conserved. Ninety-nine percent of the genic sequences were present in both genotypes and the fraction of unique genes ranged from 0.4 to 0.7%. CONCLUSIONS: This comparative analysis of two high-quality chromosome assemblies enabled a comprehensive assessment of large structural variations and gene content. The insight obtained from this analysis will form the basis of future wheat pan-genome studies.


Assuntos
Cromossomos de Plantas/genética , Genoma de Planta , Análise de Sequência de DNA , Triticum/genética , Pareamento de Bases/genética , Troca Genética , Quebras de DNA de Cadeia Dupla , Variações do Número de Cópias de DNA/genética , Reparo do DNA/genética , Fluxo Gênico , Genes de Plantas , Haplótipos/genética , Família Multigênica , Polimorfismo de Nucleotídeo Único/genética , Deleção de Sequência/genética , Sintenia/genética
16.
BMC Bioinformatics ; 19(1): 189, 2018 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-29843602

RESUMO

BACKGROUND: Genome annotation is of key importance in many research questions. The identification of protein-coding genes is often based on transcriptome sequencing data, ab-initio or homology-based prediction. Recently, it was demonstrated that intron position conservation improves homology-based gene prediction, and that experimental data improves ab-initio gene prediction. RESULTS: Here, we present an extension of the gene prediction program GeMoMa that utilizes amino acid sequence conservation, intron position conservation and optionally RNA-seq data for homology-based gene prediction. We show on published benchmark data for plants, animals and fungi that GeMoMa performs better than the gene prediction programs BRAKER1, MAKER2, and CodingQuarry, and purely RNA-seq-based pipelines for transcript identification. In addition, we demonstrate that using multiple reference organisms may help to further improve the performance of GeMoMa. Finally, we apply GeMoMa to four nematode species and to the recently published barley reference genome indicating that current annotations of protein-coding genes may be refined using GeMoMa predictions. CONCLUSIONS: GeMoMa might be of great utility for annotating newly sequenced genomes but also for finding homologs of a specific gene or gene family. GeMoMa has been published under GNU GPL3 and is freely available at http://www.jstacs.de/index.php/GeMoMa .


Assuntos
Perfilação da Expressão Gênica , Genes Fúngicos , Genes de Plantas , Análise de Sequência de RNA , Homologia de Sequência de Aminoácidos , Software , Animais , Genômica , Hordeum/genética , Íntrons , Anotação de Sequência Molecular , Nematoides/genética
17.
Plant J ; 93(3): 502-514, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29205595

RESUMO

Pseudogenes have a reputation of being 'evolutionary relics' or 'junk DNA'. While they are well characterized in mammals, studies in more complex plant genomes have so far been hampered by the absence of reference genome sequences. Barley is one of the economically most important cereals and has a genome size of 5.1 Gb. With the first high-quality genome reference assembly available for a Triticeae crop, we conducted a whole-genome assessment of pseudogenes on the barley genome. We identified, characterized and classified 89 440 gene fragments and pseudogenes scattered along the chromosomes, with occasional hotspots and higher densities at the chromosome ends. Full-length pseudogenes (11 015) have preferentially retained their exon-intron structure. Retrotransposition of processed mRNAs only plays a marginal role in their creation. However, the distribution of retroposed pseudogenes reflects the Rabl configuration of barley chromosomes and thus hints at founding mechanisms. While parent genes related to the defense-response were found to be under-represented in cultivated barley, we detected several defense-related pseudogenes in wild barley accessions. The percentage of transcriptionally active pseudogenes is 7.2%, and these may potentially adopt new regulatory roles.The barley genome is rich in pseudogenes and small gene fragments mainly located towards chromosome tips or as tandemly repeated units. Our results indicate non-random duplication and pseudogenization preferences and improve our understanding of the dynamics of gene birth and death in large plant genomes and the mechanisms that lead to evolutionary innovations.


Assuntos
Genes de Plantas , Hordeum/genética , Pseudogenes , Mapeamento Cromossômico , Cromossomos de Plantas , Duplicação Gênica , Família Multigênica , Seleção Genética , Sintenia
18.
Mob DNA ; 8: 22, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29270235

RESUMO

BACKGROUND: While transposable elements (TEs) comprise the bulk of plant genomic DNA, how they contribute to genome structure and organization is still poorly understood. Especially in large genomes where TEs make the majority of genomic DNA, it is still unclear whether TEs target specific chromosomal regions or whether they simply accumulate where they are best tolerated. RESULTS: Here, we present an analysis of the repetitive fraction of the 5100 Mb barley genome, the largest angiosperm genome to have a near-complete sequence assembly. Genes make only about 2% of the genome, while over 80% is derived from TEs. The TE fraction is composed of at least 350 different families. However, 50% of the genome is comprised of only 15 high-copy TE families, while all other TE families are present in moderate or low copy numbers. We found that the barley genome is highly compartmentalized with different types of TEs occupying different chromosomal "niches", such as distal, interstitial, or proximal regions of chromosome arms. Furthermore, gene space represents its own distinct genomic compartment that is enriched in small non-autonomous DNA transposons, suggesting that these TEs specifically target promoters and downstream regions. Furthermore, their presence in gene promoters is associated with decreased methylation levels. CONCLUSIONS: Our data show that TEs are major determinants of overall chromosome structure. We hypothesize that many of the the various chromosomal distribution patterns are the result of TE families targeting specific niches, rather than them accumulating where they have the least deleterious effects.

19.
Nature ; 551(7681): 498-502, 2017 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-29143815

RESUMO

Aegilops tauschii is the diploid progenitor of the D genome of hexaploid wheat (Triticum aestivum, genomes AABBDD) and an important genetic resource for wheat. The large size and highly repetitive nature of the Ae. tauschii genome has until now precluded the development of a reference-quality genome sequence. Here we use an array of advanced technologies, including ordered-clone genome sequencing, whole-genome shotgun sequencing, and BioNano optical genome mapping, to generate a reference-quality genome sequence for Ae. tauschii ssp. strangulata accession AL8/78, which is closely related to the wheat D genome. We show that compared to other sequenced plant genomes, including a much larger conifer genome, the Ae. tauschii genome contains unprecedented amounts of very similar repeated sequences. Our genome comparisons reveal that the Ae. tauschii genome has a greater number of dispersed duplicated genes than other sequenced genomes and its chromosomes have been structurally evolving an order of magnitude faster than those of other grass genomes. The decay of colinearity with other grass genomes correlates with recombination rates along chromosomes. We propose that the vast amounts of very similar repeated sequences cause frequent errors in recombination and lead to gene duplications and structural chromosome changes that drive fast genome evolution.


Assuntos
Genoma de Planta , Filogenia , Poaceae/genética , Triticum/genética , Mapeamento Cromossômico , Diploide , Evolução Molecular , Duplicação Gênica , Genes de Plantas/genética , Genômica/normas , Poaceae/classificação , Recombinação Genética/genética , Análise de Sequência de DNA/normas , Triticum/classificação
20.
Plant Physiol ; 175(3): 1203-1219, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28935841

RESUMO

Plants possessing dysfunctional plastids due to defects in pigment biosynthesis or translation are known to repress photosynthesis-associated nuclear genes via retrograde signals from the disturbed organelles toward the nucleus. These signals are thought to be essential for proper biogenesis and function of the plastid. Mutants lacking plastid-encoded RNA polymerase-associated proteins (PAPs) display a genetic arrest in eoplast-chloroplast transition leading to an albino phenotype in the light. Retrograde signaling in these mutants, therefore, could be expected to be similar as under conditions inducing plastid dysfunction. To answer this question, we performed plastome- and genomewide array analyses in the pap7-1 mutant of Arabidopsis (Arabidopsis thaliana). In parallel, we determined the potential overlap with light-regulated expression networks. To this end, we performed a comparative expression profiling approach using light- and dark-grown wild-type plants as relative control for the expression profiles obtained from light-grown pap7-1 mutants. Our data indicate a specific impact of retrograde signals on metabolism-related genes in pap7-1 mutants reflecting the starvation situation of the albino seedlings. In contrast, light regulation of PhANGs and other nuclear gene groups appears to be fully functional in this mutant, indicating that a block in chloroplast biogenesis per se does not repress expression of them as suggested by earlier studies. Only genes for light harvesting complex proteins displayed a significant repression indicating an exclusive retrograde impact on this gene family. Our results indicate that chloroplasts and arrested plastids each emit specific signals that control different target gene modules both in positive and negative manner.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Proteínas de Cloroplastos/genética , Genes de Plantas , Luz , Metiltransferases/genética , Mutação/genética , Plastídeos/metabolismo , Transdução de Sinais , Proteínas de Arabidopsis/metabolismo , Análise por Conglomerados , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Ontologia Genética , Redes Reguladoras de Genes , Modelos Biológicos , Morfogênese/efeitos da radiação , Fotossíntese/genética , Fotossíntese/efeitos da radiação , Plastídeos/efeitos da radiação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos da radiação
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