RESUMO
Bread wheat derives from a grass ancestor structured in seven protochromosomes followed by a paleotetraploidization to reach a 12 chromosomes intermediate and a neohexaploidization (involving subgenomes A, B and D) event that finally shaped the 21 modern chromosomes. Insights into wheat syntenome in sequencing conserved orthologous set (COS) genes unravelled differences in genomic structure (such as gene conservation and diversity) and genetical landscape (such as recombination pattern) between ancestral as well as recent duplicated blocks. Contrasted evolutionary plasticity is observed where the B subgenome appears more sensitive (i.e. plastic) in contrast to A as dominant (i.e. stable) in response to the neotetraploidization and D subgenome as supra-dominant (i.e. pivotal) in response to the neohexaploidization event. Finally, the wheat syntenome, delivered through a public web interface PlantSyntenyViewer at http://urgi.versailles.inra.fr/synteny-wheat, can be considered as a guide for accelerated dissection of major agronomical traits in wheat.
Assuntos
Cromossomos de Plantas/genética , Evolução Molecular , Genoma de Planta/genética , Genômica , Sintenia/genética , Triticum/genética , Sequência Conservada , DNA de Plantas/química , DNA de Plantas/genética , Genes Dominantes , Marcadores Genéticos , Modelos Biológicos , Polimorfismo de Nucleotídeo Único , Poliploidia , Análise de Sequência de DNARESUMO
RNA-seq experiments are now routinely used for the large scale sequencing of transcripts. In bacteria or archaea, such deep sequencing experiments typically produce 10-50 million fragments that cover most of the genome, including intergenic regions. In this context, the precise delineation of the non-coding elements is challenging. Non-coding elements include untranslated regions (UTRs) of mRNAs, independent small RNA genes (sRNAs) and transcripts produced from the antisense strand of genes (asRNA). Here we present a computational pipeline (DETR'PROK: detection of ncRNAs in prokaryotes) based on the Galaxy framework that takes as input a mapping of deep sequencing reads and performs successive steps of clustering, comparison with existing annotation and identification of transcribed non-coding fragments classified into putative 5' UTRs, sRNAs and asRNAs. We provide a step-by-step description of the protocol using real-life example data sets from Vibrio splendidus and Escherichia coli.
Assuntos
Biologia Computacional/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , RNA Mensageiro/isolamento & purificação , RNA não Traduzido/isolamento & purificação , Archaea/genética , Bactérias/genética , Sequência de Bases , RNA Mensageiro/genética , RNA não Traduzido/genéticaRESUMO
MOTIVATION: In 2005, researchers from the French National Research Institute for Agriculture, Food and Environment (Institut national de recherche pour l'agriculture, l'alimentation et l'environnement, INRAE) started a collaboration with the French farmers' seed network Réseau Semences Paysannes (RSP) on bread wheat participatory breeding (PPB). The aims were: (1) to study on-farm management of crop diversity, (2) to develop population-varieties adapted to organic and low-inputs agriculture, (3) to co-develop tools and methods adapted to on-farm experiments. In this project, researchers and farmers' organizations needed to map the history and life cycle of the population-varieties using network formalism to represent relationships between seed lots. All this information had to be centralized and stored in a database. RESULTS: We describe here SHiNeMaS (Seeds History and Network Management System) a web tool database. SHiNeMaS aims to provide useful interfaces to track seed lot history and related data (phenotyping, environment, cultural practices). Although SHiNeMaS has been developed in the context of a bread wheat participatory breeding program, the database has been designed to manage any kind and even multiple cultivated plant species. SHiNeMaS is available under Affero GPL licence and uses free technologies such as the Python language, Django framework or PostgreSQL database management system (DBMS). CONCLUSION: We developed SHiNeMaS, a web tool database, dedicated to the management of the history of seed lots and related data like phenotyping, environmental information and cultural practices. SHiNeMaS has been used in production in our laboratory for 5 years and farmers' organizations facilitators manage their own information in the system.
RESUMO
The Wheat@URGI portal has been developed to provide the international community of researchers and breeders with access to the bread wheat reference genome sequence produced by the International Wheat Genome Sequencing Consortium. Genome browsers, BLAST, and InterMine tools have been established for in-depth exploration of the genome sequence together with additional linked datasets including physical maps, sequence variations, gene expression, and genetic and phenomic data from other international collaborative projects already stored in the GnpIS information system. The portal provides enhanced search and browser features that will facilitate the deployment of the latest genomics resources in wheat improvement.
Assuntos
Genoma de Planta , Análise de Sequência de DNA , Triticum/genética , Sequência de Bases , Pão , Mineração de Dados , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Fenótipo , Padrões de ReferênciaRESUMO
The genome sequences of many important Triticeae species, including bread wheat ( L.) and barley ( L.), remained uncharacterized for a long time because their high repeat content, large sizes, and polyploidy. As a result of improvements in sequencing technologies and novel analyses strategies, several of these have recently been deciphered. These efforts have generated new insights into Triticeae biology and genome organization and have important implications for downstream usage by breeders, experimental biologists, and comparative genomicists. transPLANT () is an EU-funded project aimed at constructing hardware, software, and data infrastructure for genome-scale research in the life sciences. Since the Triticeae data are intrinsically complex, heterogenous, and distributed, the transPLANT consortium has undertaken efforts to develop common data formats and tools that enable the exchange and integration of data from distributed resources. Here we present an overview of the individual Triticeae genome resources hosted by transPLANT partners, introduce the objectives of transPLANT, and outline common developments and interfaces supporting integrated data access.
Assuntos
Genoma de Planta , Genômica/métodos , Poaceae/genética , Evolução Molecular , Hordeum/genética , Poliploidia , Triticum/genéticaRESUMO
The 1.5 Gbp/2C genome of pedunculate oak (Quercus robur) has been sequenced. A strategy was established for dealing with the challenges imposed by the sequencing of such a large, complex and highly heterozygous genome by a whole-genome shotgun (WGS) approach, without the use of costly and time-consuming methods, such as fosmid or BAC clone-based hierarchical sequencing methods. The sequencing strategy combined short and long reads. Over 49 million reads provided by Roche 454 GS-FLX technology were assembled into contigs and combined with shorter Illumina sequence reads from paired-end and mate-pair libraries of different insert sizes, to build scaffolds. Errors were corrected and gaps filled with Illumina paired-end reads and contaminants detected, resulting in a total of 17,910 scaffolds (>2 kb) corresponding to 1.34 Gb. Fifty per cent of the assembly was accounted for by 1468 scaffolds (N50 of 260 kb). Initial comparison with the phylogenetically related Prunus persica gene model indicated that genes for 84.6% of the proteins present in peach (mean protein coverage of 90.5%) were present in our assembly. The second and third steps in this project are genome annotation and the assignment of scaffolds to the oak genetic linkage map. In accordance with the Bermuda and Fort Lauderdale agreements and the more recent Toronto Statement, the oak genome data have been released into public sequence repositories in advance of publication. In this presubmission paper, the oak genome consortium describes its principal lines of work and future directions for analyses of the nature, function and evolution of the oak genome.
Assuntos
Genoma de Planta , Quercus/genética , Modelos Genéticos , Anotação de Sequência Molecular , Filogenia , Quercus/classificação , Análise de Sequência de DNARESUMO
We used nine complete genome sequences, from grape, poplar, Arabidopsis, soybean, lotus, apple, strawberry, cacao, and papaya, to investigate the paleohistory of rosid crops. We characterized an ancestral rosid karyotype, structured into 7/21 protochomosomes, with a minimal set of 6,250 ordered protogenes and a minimum physical coding gene space of 50 megabases. We also proposed ancestral karyotypes for the Caricaceae, Brassicaceae, Malvaceae, Fabaceae, Rosaceae, Salicaceae, and Vitaceae families with 9, 8, 10, 6, 12, 9, 12, and 19 protochromosomes, respectively. On the basis of these ancestral karyotypes and present-day species comparisons, we proposed a two-step evolutionary scenario based on allohexaploidization involving the newly characterized A, B, and C diploid progenitors leading to dominant (stable) and sensitive (plastic) genomic compartments in any modern rosid crops. Finally, a new user-friendly online tool, "DicotSyntenyViewer" (available from http://urgi.versailles.inra.fr/synteny-dicot), has been made available for accurate translational genomics in rosids.
Assuntos
Produtos Agrícolas/genética , Evolução Molecular , Ordem dos Genes , Genoma de Planta , Cariótipo , Magnoliopsida/genética , Cromossomos de Plantas , Duplicação Gênica , Genômica , Magnoliopsida/classificação , Filogenia , Poliploidia , SinteniaRESUMO
Modern plant genomes are diploidized paleopolyploids. We revisited grass genome paleohistory in response to the diploidization process through a detailed investigation of the evolutionary fate of duplicated blocks. Ancestrally duplicated genes can be conserved, deleted, and shuffled, defining dominant (bias toward duplicate retention) and sensitive (bias toward duplicate erosion) chromosomal fragments. We propose a new grass genome paleohistory deriving from an ancestral karyotype structured in seven protochromosomes containing 16,464 protogenes and following evolutionary rules where 1) ancestral shared polyploidizations shaped conserved dominant (D) and sensitive (S) subgenomes, 2) subgenome dominance is revealed by both gene deletion and shuffling from the S blocks, 3) duplicate deletion/movement may have been mediated by single-/double-stranded illegitimate recombination mechanisms, 4) modern genomes arose through centromeric fusion of protochromosomes, leading to functional monocentric neochromosomes, 5) the fusion of two dominant blocks leads to supradominant neochromosomes (D + D = D) with higher ancestral gene retention compared with D + S = D (i.e., fusion of blocks with opposite sensitivity) or even S + S = S (i.e., fusion of two sensitive ancestral blocks). A new user-friendly online tool named "PlantSyntenyViewer," available at http://urgi.versailles.inra.fr/synteny-cereal, presents the refined comparative genomics data.
Assuntos
Evolução Molecular , Genes Dominantes , Genes de Plantas , Poaceae/genética , Poliploidia , Software , Cromossomos de Plantas , Deleção de Genes , Duplicação Gênica , Genômica/métodos , Cariótipo , Filogenia , Recombinação GenéticaRESUMO
Data integration is a key challenge for modern bioinformatics. It aims to provide biologists with tools to explore relevant data produced by different studies. Large-scale international projects can generate lots of heterogeneous and unrelated data. The challenge is to integrate this information with other publicly available data. Nucleotide sequencing throughput has been improved with new technologies; this increases the need for powerful information systems able to store, manage and explore data. GnpIS is a multispecies integrative information system dedicated to plant and fungi pests. It bridges genetic and genomic data, allowing researchers access to both genetic information (e.g. genetic maps, quantitative trait loci, markers, single nucleotide polymorphisms, germplasms and genotypes) and genomic data (e.g. genomic sequences, physical maps, genome annotation and expression data) for species of agronomical interest. GnpIS is used by both large international projects and plant science departments at the French National Institute for Agricultural Research. Here, we illustrate its use. Database URL: http://urgi.versailles.inra.fr/gnpis.
Assuntos
Bases de Dados Genéticas , Fungos/genética , Genoma Fúngico/genética , Genoma de Planta/genética , Genômica , Plantas/genética , Cooperação Internacional , Ferramenta de Busca , Triticum/genéticaRESUMO
Plant-parasitic nematodes are major agricultural pests worldwide and novel approaches to control them are sorely needed. We report the draft genome sequence of the root-knot nematode Meloidogyne incognita, a biotrophic parasite of many crops, including tomato, cotton and coffee. Most of the assembled sequence of this asexually reproducing nematode, totaling 86 Mb, exists in pairs of homologous but divergent segments. This suggests that ancient allelic regions in M. incognita are evolving toward effective haploidy, permitting new mechanisms of adaptation. The number and diversity of plant cell wall-degrading enzymes in M. incognita is unprecedented in any animal for which a genome sequence is available, and may derive from multiple horizontal gene transfers from bacterial sources. Our results provide insights into the adaptations required by metazoans to successfully parasitize immunocompetent plants, and open the way for discovering new antiparasitic strategies.