Valentin Guignon

Mr. Valentin Guignon

Alliance Bioversity International and CIAT, Rome, Lazio, Italy
orcid

Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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19 April 2008 in Nucleic Acids Research
Verified
Journal Article
Open access
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ADA. Dereeper
A. Dereeper
VGValentin Guignon
Valentin Guignon
GBGuillaume Blanc
Guillaume Blanc
SAS. Audic
S. Audic
SBS. Buffet
S. Buffet
OGO. Gascuel
O. Gascuel
Phylogenetic analyses are central to many research areas in biology and typically involve the identification of homologous sequences, their multiple alignment, the phylogenetic reconstruction and the graphical representation of the inferred tree. The Phylogeny.fr platform transparently chains programs to automatically perform these tasks. It is primarily designed for biologists with no experience in phylogeny, but can also meet the needs of specialists; the first ones will find up-to-date tools chained in a phylogeny pipeline to analyze their data in a simple and robust way, while the specialists will be able to easily build and run sophisticated analyses. Phylogeny.fr offers three main modes. The ‘One Click’ mode targets non-specialists and provides a ready-to-use pipeline chaining programs with recognized accuracy and speed: MUSCLE for multiple alignment, PhyML for tree building, and TreeDyn for tree rendering. All parameters are set up to suit most studies, and users only have to provide their input sequences to obtain a ready-to-print tree. The ‘Advanced’ mode uses the same pipeline but allows the parameters of each program to be customized by users. The ‘A la Carte’ mode offers more flexibility and sophistication, as users can build their own pipeline by selecting and setting up the required steps from a large choice of tools to suit their specific needs. Prior to phylogenetic analysis, users can also collect neighbors of a query sequence by running BLAST on general or specialized databases. A guide tree then helps to select neighbor sequences to be used as input for the phylogeny pipeline. Phylogeny.fr is available at: http://www.phylogeny.fr/

11 July 2012 in Nature
Verified
Journal Article
Open access
ADAngélique D’hont
Angélique D’hont
FDFrance Denoeud
France Denoeud
JAJean-Marc Aury
Jean-Marc Aury
FBFranc-Christophe Baurens
Franc-Christophe Baurens
FCFrançoise Carreel
Françoise Carreel
PWPatrick Wincker
Patrick Wincker
Bananas (Musa spp.), including dessert and cooking types, are giant perennial monocotyledonous herbs of the order Zingiberales, a sister group to the well-studied Poales, which include cereals. Bananas are vital for food security in many tropical and subtropical countries and the most popular fruit in industrialized countries. The Musa domestication process started some 7,000 years ago in Southeast Asia. It involved hybridizations between diverse species and subspecies, fostered by human migrations, and selection of diploid and triploid seedless, parthenocarpic hybrids thereafter widely dispersed by vegetative propagation. Half of the current production relies on somaclones derived from a single triploid genotype (Cavendish). Pests and diseases have gradually become adapted, representing an imminent danger for global banana production. Here we describe the draft sequence of the 523-megabase genome of a Musa acuminata doubled-haploid genotype, providing a crucial stepping-stone for genetic improvement of banana. We detected three rounds of whole-genome duplications in the Musa lineage, independently of those previously described in the Poales lineage and the one we detected in the Arecales lineage. This first monocotyledon high-continuity whole-genome sequence reported outside Poales represents an essential bridge for comparative genome analysis in plants. As such, it clarifies commelinid-monocotyledon phylogenetic relationships, reveals Poaceae-specific features and has led to the discovery of conserved non-coding sequences predating monocotyledon-eudicotyledon divergence.

26 December 2010 in Nature Genetics
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XAXavier Argout
Xavier Argout
JSJerome Salse
Jerome Salse
JAJean-Marc Aury
Jean-Marc Aury
MGMark J Guiltinan
Mark J Guiltinan
GDGaetan Droc
Gaetan Droc
CLClaire Lanaud
Claire Lanaud
We sequenced and assembled the draft genome of Theobroma cacao, an economically important tropical-fruit tree crop that is the source of chocolate. This assembly corresponds to 76% of the estimated genome size and contains almost all previously described genes, with 82% of these genes anchored on the 10 T. cacao chromosomes. Analysis of this sequence information highlighted specific expansion of some gene families during evolution, for example, flavonoid-related genes. It also provides a major source of candidate genes for T. cacao improvement. Based on the inferred paleohistory of the T. cacao genome, we propose an evolutionary scenario whereby the ten T. cacao chromosomes were shaped from an ancestor through eleven chromosome fusions.

5 September 2014 in Science
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Journal Article
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FDFrance Denoeud
France Denoeud
LCLorenzo Carretero-Paulet
Lorenzo Carretero-Paulet
ADAlexis Dereeper
Alexis Dereeper
GDGaëtan Droc
Gaëtan Droc
RGRomain Guyot
Romain Guyot
PLPhilippe Lashermes
Philippe Lashermes
Coffee, tea, and chocolate converge: Caffeine has evolved multiple times among plant species, but no one knows whether these events involved similar genes. Denoeudet al.sequenced theCoffea canephora(coffee) genome and identified a conserved gene order (see the Perspective by Zamir). Although this species underwent fewer genome duplications than related species, the relevant caffeine genes experienced tandem duplications that expanded their numbers within this species. Scientists have seen similar but independent expansions in distantly related species of tea and cacao, suggesting that caffeine might have played an adaptive role in coffee evolution.Science, this issue p.1181; see also p.1124

1 January 2013 in Database: The Journal of Biological Databases and Curation
Verified
Journal Article
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GDGaëtan Droc
Gaëtan Droc
DLDelphine Larivière
Delphine Larivière
VGValentin Guignon
Valentin Guignon
NYNabila Yahiaoui
Nabila Yahiaoui
DTDominique This
Dominique This
SBStéphanie Bocs
Stéphanie Bocs
Banana is one of the world’s favorite fruits and one of the most important crops for developing countries. The banana reference genome sequence (Musa acuminata) was recently released. Given the taxonomic position of Musa, the completed genomic sequence has particular comparative value to provide fresh insights about the evolution of the monocotyledons. The study of the banana genome has been enhanced by a number of tools and resources that allows harnessing its sequence. First, we set up essential tools such as a Community Annotation System, phylogenomics resources and metabolic pathways. Then, to support post-genomic efforts, we improved banana existing systems (e.g. web front end, query builder), we integrated available Musa data into generic systems (e.g. markers and genetic maps, synteny blocks), we have made interoperable with the banana hub, other existing systems containing Musa data (e.g. transcriptomics, rice reference genome, workflow manager) and finally, we generated new results from sequence analyses (e.g. SNP and polymorphism analysis). Several uses cases illustrate how the Banana Genome Hub can be used to study gene families. Overall, with this collaborative effort, we discuss the importance of the interoperability toward data integration between existing information systems. Database URL: http://banana-genome.cirad.fr/

22 September 2010 in Nucleic Acids Research
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Journal Article
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MRMathieu Rouard
Mathieu Rouard
VGValentin Guignon
Valentin Guignon
CAChristelle Aluome
Christelle Aluome
MLMarie-Angélique Laporte
Marie-Angélique Laporte
GDGaëtan Droc
Gaëtan Droc
MCMatthieu G. Conte
Matthieu G. Conte
GreenPhylDB is a database designed for comparative and functional genomics based on complete genomes. Version 2 now contains sixteen full genomes of members of the plantae kingdom, ranging from algae to angiosperms, automatically clustered into gene families. Gene families are manually annotated and then analyzed phylogenetically in order to elucidate orthologous and paralogous relationships. The database offers various lists of gene families including plant, phylum and species specific gene families. For each gene cluster or gene family, easy access to gene composition, protein domains, publications, external links and orthologous gene predictions is provided. Web interfaces have been further developed to improve the navigation through information related to gene families. New analysis tools are also available, such as a gene family ontology browser that facilitates exploration. GreenPhylDB is a component of the South Green Bioinformatics Platform ( http://southgreen.cirad.fr/ ) and is accessible at http://greenphyl.cirad.fr . It enables comparative genomics in a broad taxonomy context to enhance the understanding of evolutionary processes and thus tends to speed up gene discovery.