The Experts below are selected from a list of 4716 Experts worldwide ranked by ideXlab platform
P. Arce-johnson - One of the best experts on this subject based on the ideXlab platform.
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Gene expression associated with compatible viral diseases in grapevine Cultivars
Functional & Integrative Genomics, 2007Co-Authors: C. Espinoza, A. Vega, C. Medina, K. Schlauch, G. Cramer, P. Arce-johnsonAbstract:Viral diseases affect grapevine cultures without inducing any resistance response. Thus, these plants develop systemic diseases and are chronically infected. Molecular events associated with viral compatible infections responsible for disease establishment and symptoms development are poorly understood. In this study, we surveyed viral infection in grapevines at a transcriptional level. Gene expression in the Vitis vinifera red Wine Cultivars Carménère and Cabernet-Sauvignon naturally infected with GLRaV-3 were evaluated using a genome-wide expression profiling with the Vitis vinifera GeneChip^® from Affymetrix. We describe numerous genes that are induced or repressed in viral infected grapevines leaves. Changes in gene expression involved a wide spectrum of biological functions, including processes of translation and protein targeting, metabolism, transport, and cell defense. Considering cellular localization, the membrane and endomembrane systems appeared with the highest number of induced genes, while chloroplastic genes were mostly repressed. As most induced genes associated with the membranous system are involved in transport, the possible effect of virus in this process is discussed. Responses of both Cultivars are analyzed and the results are compared with published data from other species. This is the first study of global gene profiling in grapevine in response to viral infections using DNA microarray.
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Gene expression associated with compatible viral diseases in grapevine Cultivars.
Functional & integrative genomics, 2006Co-Authors: C. Espinoza, A. Vega, C. Medina, K. Schlauch, Grant R. Cramer, P. Arce-johnsonAbstract:Viral diseases affect grapevine cultures without inducing any resistance response. Thus, these plants develop systemic diseases and are chronically infected. Molecular events associated with viral compatible infections responsible for disease establishment and symptoms development are poorly understood. In this study, we surveyed viral infection in grapevines at a transcriptional level. Gene expression in the Vitis vinifera red Wine Cultivars Carmenere and Cabernet-Sauvignon naturally infected with GLRaV-3 were evaluated using a genome-wide expression profiling with the Vitis vinifera GeneChip® from Affymetrix. We describe numerous genes that are induced or repressed in viral infected grapevines leaves. Changes in gene expression involved a wide spectrum of biological functions, including processes of translation and protein targeting, metabolism, transport, and cell defense. Considering cellular localization, the membrane and endomembrane systems appeared with the highest number of induced genes, while chloroplastic genes were mostly repressed. As most induced genes associated with the membranous system are involved in transport, the possible effect of virus in this process is discussed. Responses of both Cultivars are analyzed and the results are compared with published data from other species. This is the first study of global gene profiling in grapevine in response to viral infections using DNA microarray.
Patrice This - One of the best experts on this subject based on the ideXlab platform.
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A novel high-density grapevine (Vitis vinifera L.) integrated linkage map using GBS in a half-diallel population
Theoretical and Applied Genetics, 2019Co-Authors: Javier Tello, Valerie Laucou, Catherine Roux, Hajar Chouiki, Gautier Sarah, Audrey Weber, Sylvain Santoni, Timothée Flutre, Thierry Pons, Patrice ThisAbstract:Key message A half-diallel population involving five elite grapevine Cultivars was generated and genotyped by GBS, and highly-informative segregation data was used to construct a high-density genetic map for Vitis vinifera L. Abstract Grapevine is one of the most relevant fruit crops in the world. Deeper genetic knowledge could assist modern grapevine breeding programs to develop new Wine grape varieties able to face climate change effects. To assist in the rapid identification of markers for crop yield components, grape quality traits and adaptation potential, we generated a large Vitis vinifera L. population ( N = 624) by crossing five red Wine Cultivars in a half-diallel scheme, which was subsequently sequenced by an efficient GBS procedure. A high number of fully informative genetic variants was detected using a novel mapping approach capable of reconstructing local haplotypes from adjacent biallelic SNPs, which were subsequently used to construct the densest consensus genetic map available for the cultivated grapevine to date. This 1378.3-cM map integrates 10 bi-parental consensus maps and orders 4437 markers in 3353 unique positions on 19 chromosomes. Markers are well distributed all along the grapevine reference genome, covering up to 98.8% of its genomic sequence. Additionally, a good agreement was observed between genetic and physical orders, adding confidence in the quality of this map. Collectively, our results pave the way for future genetic studies (such as fine QTL mapping) aimed to understand the complex relationship between genotypic and phenotypic variation in the cultivated grapevine. In addition, the method used (which efficiently delivers a high number of fully informative markers) could be of interest to other outbred organisms, notably perennial fruit crops.
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Haplotype diversity of VvTFL1A gene and association with cluster traits in grapevine (V. vinifera)
BMC plant biology, 2014Co-Authors: Lucie Fernandez, Thierry Lacombe, Loic Le Cunff, Jean-michel Boursiquot, Javier Tello, Alexandre Fournier-level, Gema Bravo, Sandrine Lalet, Laurent Torregrosa, Patrice ThisAbstract:Background: Interaction between TERMINAL FLOWER 1 (TFL1) and LEAFY (LFY) seem to determine the inflorescence architecture in Arabidopsis. In a parallel way, overexpression of VvTFL1A, a grapevine TFL1 homolog, causes delayed flowering and production of a ramose cluster in the reiterated reproductive meristem (RRM) somatic variant of cultivar Carignan. To analyze the possible contribution of this gene to cluster phenotypic variation in a diversity panel of cultivated grapevine (Vitis vinifera L. subsp. vinifera) its nucleotide diversity was characterized and association analyses among detected sequence polymorphisms and phenology and cluster traits was carried out. Results: A total of 3.6 kb of the VvTFL1A gene, including its promoter, was sequenced in a core collection of 140 individuals designed to maximize phenotypic variation at agronomical relevant traits. Nucleotide variation for VvTFL1A within this collection was higher in the promoter and intron sequences than in the exon regions; where few polymorphisms were located in agreement with a high conservation of coding sequence. Characterization of the VvTFL1A haplotype network identified three major haplogroups, consistent with the geographic origins and the use of the Cultivars that could correspond to three major ancestral alleles or evolutionary branches, based on the existence of mutations in linkage disequilibrium. Genetic association studies with cluster traits revealed the presence of major INDEL polymorphisms, explaining 16%, 13% and 25% of flowering time, cluster width and berry weight, respectively, and also structuring the three haplogroups. Conclusions: At least three major VvTFL1A haplogroups are present in cultivated grapevines, which are defined by the presence of three main polymorphism LD blocks and associated to characteristic phenotypic values for flowering time, cluster width and berry size. Phenotypic differences between haplogroups are consistent with differences observed between Eastern and Western grapevine Cultivars and could result from the use of different genetic pools in the domestication process as well as different selection pressures on the development of table and Wine Cultivars, respectively. Altogether, these results are coherent with previous classifications of grapevine phenotypic diversity mainly based on cluster and berry morphotypes as well as with recent results on the structure of genetic diversity in cultivated grapevine.
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Genetic structure in cultivated grapevines is linked to geography and human selection.
BMC Plant Biology, 2013Co-Authors: Roberto Bacilieri, Thierry Lacombe, Loic Le Cunff, Manuel Di Vecchi-staraz, Valerie Laucou, Blaise Genna, Jean-pierre Peros, Patrice This, Jean-michel BoursiquotAbstract:Background - Grapevine (Vitis vinifera subsp. vinifera) is one of the most important and ancient horticultural plants in the world. Domesticated about 8--10,000 years ago in the Eurasian region, grapevine evolved from its wild relative (V. vinifera subsp. sylvestris) into very diverse and heterozygous cultivated forms. In this work we study grapevine genetic structure in a large sample of cultivated varieties, to interpret the wide diversity at morphological and molecular levels and link it to Cultivars utilization, putative geographic origin and historical events. Results - We analyzed the genetic structure of cultivated grapevine using a dataset of 2,096 multi-locus genotypes defined by 20 microsatellite markers. We used the Bayesian approach implemented in the STRUCTURE program and a hierarchical clustering procedure based on Ward's method to assign individuals to sub-groups. The analysis revealed three main genetic groups defined by human use and geographic origin: a) Wine Cultivars from western regions, b) Wine Cultivars from the Balkans and East Europe, and c) a group mainly composed of table grape Cultivars from Eastern Mediterranean, Caucasus, Middle and Far East countries. A second structure level revealed two additional groups, a geographic group from the Iberian Peninsula and Maghreb, and a group comprising table grapes of recent origins from Italy and Central Europe. A large number of admixed genotypes were also identified. Structure clusters regrouped together a large proportion of family-related genotypes. In addition, Ward's method revealed a third level of structure, corresponding either to limited geographic areas, to particular grape use or to family groups created through artificial selection and breeding. Conclusions - This study provides evidence that the cultivated compartment of Vitis vinifera L. is genetically structured. Genetic relatedness of Cultivars has been shaped mostly by human uses, in combination with a geographical effect. The finding of a large portion of admixed genotypes may be the trace of both large human-mediated exchanges between grape-growing regions throughout history and recent breeding.
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A candidate gene association study on muscat flavor in grapevine (Vitis viniferaL.)
BMC Plant Biology, 2010Co-Authors: Francesco Emanuelli, Loic Le Cunff, Patrice This, Jean-michel Boursiquot, Laura Costantini, Juri Battilana, Maria S. GrandoAbstract:Background The sweet, floral flavor typical of Muscat varieties (Muscats), due to high levels of monoterpenoids (geraniol, linalool and nerol), is highly distinct and has been greatly appreciated both in table grapes and in Wine since ancient times. Muscat flavor determination in grape ( Vitis vinifera L.) has up to now been studied by evaluating monoterpenoid levels through QTL analysis. These studies have revealed co-localization of 1-deoxy-D-xylulose 5-phosphate synthase ( VvDXS ) with the major QTL positioned on chromosome 5. Results We resequenced VvDXS in an ad hoc association population of 148 grape varieties, which included muscat-flavored, aromatic and neutral accessions as well as muscat-like aromatic mutants and non-aromatic offsprings of Muscats. Gene nucleotide diversity and intragenic linkage disequilibrium (LD) were evaluated. Structured association analysis revealed three SNPs in moderate LD to be significantly associated with muscat-flavored varieties. We identified a putative causal SNP responsible for a predicted non-neutral substitution and we discuss its possible implications for flavor metabolism. Network analysis revealed a major star-shaped cluster of reconstructed haplotypes unique to muscat-flavored varieties. Moreover, muscat-like aromatic mutants displayed unique non-synonymous mutations near the mutated site of Muscat genotypes. Conclusions This study is a crucial step forward in understanding the genetic regulation of muscat flavor in grapevine and it also sheds light on the domestication history of Muscats. VvDXS appears to be a possible human-selected locus in grapevine domestication and post-domestication. The putative causal SNP identified in Muscat varieties as well as the unique mutations identifying the muscat-like aromatic mutants under study may be immediately applied in marker-assisted breeding programs aimed at enhancing fragrance and aroma complexity respectively in table grape and Wine Cultivars.
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A candidate gene association study on muscat flavor in grapevine (Vitis vinifera L.)
BMC Plant Biology, 2010Co-Authors: Francesco Emanuelli, Loic Le Cunff, Patrice This, Jean-michel Boursiquot, Laura Costantini, Juri Battilana, Maria S. GrandoAbstract:Background: The sweet, floral flavor typical of Muscat varieties (Muscats), due to high levels of monoterpenoids (geraniol, linalool and nerol), is highly distinct and has been greatly appreciated both in table grapes and in Wine since ancient times. Muscat flavor determination in grape (Vitis vinifera L.) has up to now been studied by evaluating monoterpenoid levels through QTL analysis. These studies have revealed co-localization of 1-deoxy-D-xylulose 5-phosphate synthase (VvDXS) with the major QTL positioned on chromosome 5. Results: We resequenced VvDXS in an ad hoc association population of 148 grape varieties, which included muscat-flavored, aromatic and neutral accessions as well as muscat-like aromatic mutants and non-aromatic offsprings of Muscats. Gene nucleotide diversity and intragenic linkage disequilibrium (LD) were evaluated. Structured association analysis revealed three SNPs in moderate LD to be significantly associated with muscat-flavored varieties. We identified a putative causal SNP responsible for a predicted non-neutral substitution and we discuss its possible implications for flavor metabolism. Network analysis revealed a major star-shaped cluster of reconstructed haplotypes unique to muscat-flavored varieties. Moreover, muscat-like aromatic mutants displayed unique non-synonymous mutations near the mutated site of Muscat genotypes. Conclusions: This study is a crucial step forward in understanding the genetic regulation of muscat flavor in grapevine and it also sheds light on the domestication history of Muscats. VvDXS appears to be a possible human-selected locus in grapevine domestication and post-domestication. The putative causal SNP identified in Muscat varieties as well as the unique mutations identifying the muscat-like aromatic mutants under study may be immediately applied in marker-assisted breeding programs aimed at enhancing fragrance and aroma complexity respectively in table grape and Wine Cultivars
Jean-michel Boursiquot - One of the best experts on this subject based on the ideXlab platform.
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Haplotype diversity of VvTFL1A gene and association with cluster traits in grapevine (V. vinifera)
BMC plant biology, 2014Co-Authors: Lucie Fernandez, Thierry Lacombe, Loic Le Cunff, Jean-michel Boursiquot, Javier Tello, Alexandre Fournier-level, Gema Bravo, Sandrine Lalet, Laurent Torregrosa, Patrice ThisAbstract:Background: Interaction between TERMINAL FLOWER 1 (TFL1) and LEAFY (LFY) seem to determine the inflorescence architecture in Arabidopsis. In a parallel way, overexpression of VvTFL1A, a grapevine TFL1 homolog, causes delayed flowering and production of a ramose cluster in the reiterated reproductive meristem (RRM) somatic variant of cultivar Carignan. To analyze the possible contribution of this gene to cluster phenotypic variation in a diversity panel of cultivated grapevine (Vitis vinifera L. subsp. vinifera) its nucleotide diversity was characterized and association analyses among detected sequence polymorphisms and phenology and cluster traits was carried out. Results: A total of 3.6 kb of the VvTFL1A gene, including its promoter, was sequenced in a core collection of 140 individuals designed to maximize phenotypic variation at agronomical relevant traits. Nucleotide variation for VvTFL1A within this collection was higher in the promoter and intron sequences than in the exon regions; where few polymorphisms were located in agreement with a high conservation of coding sequence. Characterization of the VvTFL1A haplotype network identified three major haplogroups, consistent with the geographic origins and the use of the Cultivars that could correspond to three major ancestral alleles or evolutionary branches, based on the existence of mutations in linkage disequilibrium. Genetic association studies with cluster traits revealed the presence of major INDEL polymorphisms, explaining 16%, 13% and 25% of flowering time, cluster width and berry weight, respectively, and also structuring the three haplogroups. Conclusions: At least three major VvTFL1A haplogroups are present in cultivated grapevines, which are defined by the presence of three main polymorphism LD blocks and associated to characteristic phenotypic values for flowering time, cluster width and berry size. Phenotypic differences between haplogroups are consistent with differences observed between Eastern and Western grapevine Cultivars and could result from the use of different genetic pools in the domestication process as well as different selection pressures on the development of table and Wine Cultivars, respectively. Altogether, these results are coherent with previous classifications of grapevine phenotypic diversity mainly based on cluster and berry morphotypes as well as with recent results on the structure of genetic diversity in cultivated grapevine.
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Genetic structure in cultivated grapevines is linked to geography and human selection.
BMC Plant Biology, 2013Co-Authors: Roberto Bacilieri, Thierry Lacombe, Loic Le Cunff, Manuel Di Vecchi-staraz, Valerie Laucou, Blaise Genna, Jean-pierre Peros, Patrice This, Jean-michel BoursiquotAbstract:Background - Grapevine (Vitis vinifera subsp. vinifera) is one of the most important and ancient horticultural plants in the world. Domesticated about 8--10,000 years ago in the Eurasian region, grapevine evolved from its wild relative (V. vinifera subsp. sylvestris) into very diverse and heterozygous cultivated forms. In this work we study grapevine genetic structure in a large sample of cultivated varieties, to interpret the wide diversity at morphological and molecular levels and link it to Cultivars utilization, putative geographic origin and historical events. Results - We analyzed the genetic structure of cultivated grapevine using a dataset of 2,096 multi-locus genotypes defined by 20 microsatellite markers. We used the Bayesian approach implemented in the STRUCTURE program and a hierarchical clustering procedure based on Ward's method to assign individuals to sub-groups. The analysis revealed three main genetic groups defined by human use and geographic origin: a) Wine Cultivars from western regions, b) Wine Cultivars from the Balkans and East Europe, and c) a group mainly composed of table grape Cultivars from Eastern Mediterranean, Caucasus, Middle and Far East countries. A second structure level revealed two additional groups, a geographic group from the Iberian Peninsula and Maghreb, and a group comprising table grapes of recent origins from Italy and Central Europe. A large number of admixed genotypes were also identified. Structure clusters regrouped together a large proportion of family-related genotypes. In addition, Ward's method revealed a third level of structure, corresponding either to limited geographic areas, to particular grape use or to family groups created through artificial selection and breeding. Conclusions - This study provides evidence that the cultivated compartment of Vitis vinifera L. is genetically structured. Genetic relatedness of Cultivars has been shaped mostly by human uses, in combination with a geographical effect. The finding of a large portion of admixed genotypes may be the trace of both large human-mediated exchanges between grape-growing regions throughout history and recent breeding.
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A candidate gene association study on muscat flavor in grapevine (Vitis viniferaL.)
BMC Plant Biology, 2010Co-Authors: Francesco Emanuelli, Loic Le Cunff, Patrice This, Jean-michel Boursiquot, Laura Costantini, Juri Battilana, Maria S. GrandoAbstract:Background The sweet, floral flavor typical of Muscat varieties (Muscats), due to high levels of monoterpenoids (geraniol, linalool and nerol), is highly distinct and has been greatly appreciated both in table grapes and in Wine since ancient times. Muscat flavor determination in grape ( Vitis vinifera L.) has up to now been studied by evaluating monoterpenoid levels through QTL analysis. These studies have revealed co-localization of 1-deoxy-D-xylulose 5-phosphate synthase ( VvDXS ) with the major QTL positioned on chromosome 5. Results We resequenced VvDXS in an ad hoc association population of 148 grape varieties, which included muscat-flavored, aromatic and neutral accessions as well as muscat-like aromatic mutants and non-aromatic offsprings of Muscats. Gene nucleotide diversity and intragenic linkage disequilibrium (LD) were evaluated. Structured association analysis revealed three SNPs in moderate LD to be significantly associated with muscat-flavored varieties. We identified a putative causal SNP responsible for a predicted non-neutral substitution and we discuss its possible implications for flavor metabolism. Network analysis revealed a major star-shaped cluster of reconstructed haplotypes unique to muscat-flavored varieties. Moreover, muscat-like aromatic mutants displayed unique non-synonymous mutations near the mutated site of Muscat genotypes. Conclusions This study is a crucial step forward in understanding the genetic regulation of muscat flavor in grapevine and it also sheds light on the domestication history of Muscats. VvDXS appears to be a possible human-selected locus in grapevine domestication and post-domestication. The putative causal SNP identified in Muscat varieties as well as the unique mutations identifying the muscat-like aromatic mutants under study may be immediately applied in marker-assisted breeding programs aimed at enhancing fragrance and aroma complexity respectively in table grape and Wine Cultivars.
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A candidate gene association study on muscat flavor in grapevine (Vitis vinifera L.)
BMC Plant Biology, 2010Co-Authors: Francesco Emanuelli, Loic Le Cunff, Patrice This, Jean-michel Boursiquot, Laura Costantini, Juri Battilana, Maria S. GrandoAbstract:Background: The sweet, floral flavor typical of Muscat varieties (Muscats), due to high levels of monoterpenoids (geraniol, linalool and nerol), is highly distinct and has been greatly appreciated both in table grapes and in Wine since ancient times. Muscat flavor determination in grape (Vitis vinifera L.) has up to now been studied by evaluating monoterpenoid levels through QTL analysis. These studies have revealed co-localization of 1-deoxy-D-xylulose 5-phosphate synthase (VvDXS) with the major QTL positioned on chromosome 5. Results: We resequenced VvDXS in an ad hoc association population of 148 grape varieties, which included muscat-flavored, aromatic and neutral accessions as well as muscat-like aromatic mutants and non-aromatic offsprings of Muscats. Gene nucleotide diversity and intragenic linkage disequilibrium (LD) were evaluated. Structured association analysis revealed three SNPs in moderate LD to be significantly associated with muscat-flavored varieties. We identified a putative causal SNP responsible for a predicted non-neutral substitution and we discuss its possible implications for flavor metabolism. Network analysis revealed a major star-shaped cluster of reconstructed haplotypes unique to muscat-flavored varieties. Moreover, muscat-like aromatic mutants displayed unique non-synonymous mutations near the mutated site of Muscat genotypes. Conclusions: This study is a crucial step forward in understanding the genetic regulation of muscat flavor in grapevine and it also sheds light on the domestication history of Muscats. VvDXS appears to be a possible human-selected locus in grapevine domestication and post-domestication. The putative causal SNP identified in Muscat varieties as well as the unique mutations identifying the muscat-like aromatic mutants under study may be immediately applied in marker-assisted breeding programs aimed at enhancing fragrance and aroma complexity respectively in table grape and Wine Cultivars
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genetic structure and differentiation in cultivated grape vitis vinifera l
Genetics Research, 2003Co-Authors: Mallikarjuna K Aradhya, Jean-michel Boursiquot, Gerald S Dangl, Bernard Prins, Andrew M Walker, Carole P Meredith, Charles J SimonAbstract:Summary 222 cultivated (Vitis vinifera) and 22 wild (V. vinifera ssp. sylvestris) grape accessions were analysed for genetic diversity and differentiation at eight microsatellite loci. A total of 94 alleles were detected, with extensive polymorphism among the accessions. Multivariate relationships among accessions revealed 16 genetic groups structured into three clusters, supporting the classical eco-geographic grouping of grape Cultivars : occidentalis, pontica and orientalis. French Cultivars appeared to be distinct and showed close affinity to the wild progenitor, ssp. sylvestris from south-western France (Pyrenees) and Tunisia, probably reflecting the origin and domestication history of many of the old Wine Cultivars from France. There was appreciable level of differentiation between table and Wine grape Cultivars, and the Muscat types were somewhat distinct within the Wine grapes. Contingency x 2 analysis indicated significant heterogeneity in allele frequencies among groups at all loci. The observed heterozygosities for different groups ranged from 0 . 625 to 0 . 9 with an overall average of 0 . 771. Genetic relationships among groups suggested hierarchical differentiation within cultivated grape. The gene diversity analysis indicated narrow divergence among groups and that most variation was found within groups (y85 %). Partitioning of diversity suggested that the remaining variation is somewhat structured hierarchically at different levels of differentiation. The overall organization of genetic diversity suggests that the germplasm of cultivated grape represents a single complex gene pool and that its structure is determined by strong artificial selection and a vegetative mode of reproduction.
C. Espinoza - One of the best experts on this subject based on the ideXlab platform.
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Gene expression associated with compatible viral diseases in grapevine Cultivars
Functional & Integrative Genomics, 2007Co-Authors: C. Espinoza, A. Vega, C. Medina, K. Schlauch, G. Cramer, P. Arce-johnsonAbstract:Viral diseases affect grapevine cultures without inducing any resistance response. Thus, these plants develop systemic diseases and are chronically infected. Molecular events associated with viral compatible infections responsible for disease establishment and symptoms development are poorly understood. In this study, we surveyed viral infection in grapevines at a transcriptional level. Gene expression in the Vitis vinifera red Wine Cultivars Carménère and Cabernet-Sauvignon naturally infected with GLRaV-3 were evaluated using a genome-wide expression profiling with the Vitis vinifera GeneChip^® from Affymetrix. We describe numerous genes that are induced or repressed in viral infected grapevines leaves. Changes in gene expression involved a wide spectrum of biological functions, including processes of translation and protein targeting, metabolism, transport, and cell defense. Considering cellular localization, the membrane and endomembrane systems appeared with the highest number of induced genes, while chloroplastic genes were mostly repressed. As most induced genes associated with the membranous system are involved in transport, the possible effect of virus in this process is discussed. Responses of both Cultivars are analyzed and the results are compared with published data from other species. This is the first study of global gene profiling in grapevine in response to viral infections using DNA microarray.
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Gene expression associated with compatible viral diseases in grapevine Cultivars.
Functional & integrative genomics, 2006Co-Authors: C. Espinoza, A. Vega, C. Medina, K. Schlauch, Grant R. Cramer, P. Arce-johnsonAbstract:Viral diseases affect grapevine cultures without inducing any resistance response. Thus, these plants develop systemic diseases and are chronically infected. Molecular events associated with viral compatible infections responsible for disease establishment and symptoms development are poorly understood. In this study, we surveyed viral infection in grapevines at a transcriptional level. Gene expression in the Vitis vinifera red Wine Cultivars Carmenere and Cabernet-Sauvignon naturally infected with GLRaV-3 were evaluated using a genome-wide expression profiling with the Vitis vinifera GeneChip® from Affymetrix. We describe numerous genes that are induced or repressed in viral infected grapevines leaves. Changes in gene expression involved a wide spectrum of biological functions, including processes of translation and protein targeting, metabolism, transport, and cell defense. Considering cellular localization, the membrane and endomembrane systems appeared with the highest number of induced genes, while chloroplastic genes were mostly repressed. As most induced genes associated with the membranous system are involved in transport, the possible effect of virus in this process is discussed. Responses of both Cultivars are analyzed and the results are compared with published data from other species. This is the first study of global gene profiling in grapevine in response to viral infections using DNA microarray.
Loic Le Cunff - One of the best experts on this subject based on the ideXlab platform.
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Haplotype diversity of VvTFL1A gene and association with cluster traits in grapevine (V. vinifera)
BMC plant biology, 2014Co-Authors: Lucie Fernandez, Thierry Lacombe, Loic Le Cunff, Jean-michel Boursiquot, Javier Tello, Alexandre Fournier-level, Gema Bravo, Sandrine Lalet, Laurent Torregrosa, Patrice ThisAbstract:Background: Interaction between TERMINAL FLOWER 1 (TFL1) and LEAFY (LFY) seem to determine the inflorescence architecture in Arabidopsis. In a parallel way, overexpression of VvTFL1A, a grapevine TFL1 homolog, causes delayed flowering and production of a ramose cluster in the reiterated reproductive meristem (RRM) somatic variant of cultivar Carignan. To analyze the possible contribution of this gene to cluster phenotypic variation in a diversity panel of cultivated grapevine (Vitis vinifera L. subsp. vinifera) its nucleotide diversity was characterized and association analyses among detected sequence polymorphisms and phenology and cluster traits was carried out. Results: A total of 3.6 kb of the VvTFL1A gene, including its promoter, was sequenced in a core collection of 140 individuals designed to maximize phenotypic variation at agronomical relevant traits. Nucleotide variation for VvTFL1A within this collection was higher in the promoter and intron sequences than in the exon regions; where few polymorphisms were located in agreement with a high conservation of coding sequence. Characterization of the VvTFL1A haplotype network identified three major haplogroups, consistent with the geographic origins and the use of the Cultivars that could correspond to three major ancestral alleles or evolutionary branches, based on the existence of mutations in linkage disequilibrium. Genetic association studies with cluster traits revealed the presence of major INDEL polymorphisms, explaining 16%, 13% and 25% of flowering time, cluster width and berry weight, respectively, and also structuring the three haplogroups. Conclusions: At least three major VvTFL1A haplogroups are present in cultivated grapevines, which are defined by the presence of three main polymorphism LD blocks and associated to characteristic phenotypic values for flowering time, cluster width and berry size. Phenotypic differences between haplogroups are consistent with differences observed between Eastern and Western grapevine Cultivars and could result from the use of different genetic pools in the domestication process as well as different selection pressures on the development of table and Wine Cultivars, respectively. Altogether, these results are coherent with previous classifications of grapevine phenotypic diversity mainly based on cluster and berry morphotypes as well as with recent results on the structure of genetic diversity in cultivated grapevine.
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Genetic structure in cultivated grapevines is linked to geography and human selection.
BMC Plant Biology, 2013Co-Authors: Roberto Bacilieri, Thierry Lacombe, Loic Le Cunff, Manuel Di Vecchi-staraz, Valerie Laucou, Blaise Genna, Jean-pierre Peros, Patrice This, Jean-michel BoursiquotAbstract:Background - Grapevine (Vitis vinifera subsp. vinifera) is one of the most important and ancient horticultural plants in the world. Domesticated about 8--10,000 years ago in the Eurasian region, grapevine evolved from its wild relative (V. vinifera subsp. sylvestris) into very diverse and heterozygous cultivated forms. In this work we study grapevine genetic structure in a large sample of cultivated varieties, to interpret the wide diversity at morphological and molecular levels and link it to Cultivars utilization, putative geographic origin and historical events. Results - We analyzed the genetic structure of cultivated grapevine using a dataset of 2,096 multi-locus genotypes defined by 20 microsatellite markers. We used the Bayesian approach implemented in the STRUCTURE program and a hierarchical clustering procedure based on Ward's method to assign individuals to sub-groups. The analysis revealed three main genetic groups defined by human use and geographic origin: a) Wine Cultivars from western regions, b) Wine Cultivars from the Balkans and East Europe, and c) a group mainly composed of table grape Cultivars from Eastern Mediterranean, Caucasus, Middle and Far East countries. A second structure level revealed two additional groups, a geographic group from the Iberian Peninsula and Maghreb, and a group comprising table grapes of recent origins from Italy and Central Europe. A large number of admixed genotypes were also identified. Structure clusters regrouped together a large proportion of family-related genotypes. In addition, Ward's method revealed a third level of structure, corresponding either to limited geographic areas, to particular grape use or to family groups created through artificial selection and breeding. Conclusions - This study provides evidence that the cultivated compartment of Vitis vinifera L. is genetically structured. Genetic relatedness of Cultivars has been shaped mostly by human uses, in combination with a geographical effect. The finding of a large portion of admixed genotypes may be the trace of both large human-mediated exchanges between grape-growing regions throughout history and recent breeding.
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A candidate gene association study on muscat flavor in grapevine (Vitis viniferaL.)
BMC Plant Biology, 2010Co-Authors: Francesco Emanuelli, Loic Le Cunff, Patrice This, Jean-michel Boursiquot, Laura Costantini, Juri Battilana, Maria S. GrandoAbstract:Background The sweet, floral flavor typical of Muscat varieties (Muscats), due to high levels of monoterpenoids (geraniol, linalool and nerol), is highly distinct and has been greatly appreciated both in table grapes and in Wine since ancient times. Muscat flavor determination in grape ( Vitis vinifera L.) has up to now been studied by evaluating monoterpenoid levels through QTL analysis. These studies have revealed co-localization of 1-deoxy-D-xylulose 5-phosphate synthase ( VvDXS ) with the major QTL positioned on chromosome 5. Results We resequenced VvDXS in an ad hoc association population of 148 grape varieties, which included muscat-flavored, aromatic and neutral accessions as well as muscat-like aromatic mutants and non-aromatic offsprings of Muscats. Gene nucleotide diversity and intragenic linkage disequilibrium (LD) were evaluated. Structured association analysis revealed three SNPs in moderate LD to be significantly associated with muscat-flavored varieties. We identified a putative causal SNP responsible for a predicted non-neutral substitution and we discuss its possible implications for flavor metabolism. Network analysis revealed a major star-shaped cluster of reconstructed haplotypes unique to muscat-flavored varieties. Moreover, muscat-like aromatic mutants displayed unique non-synonymous mutations near the mutated site of Muscat genotypes. Conclusions This study is a crucial step forward in understanding the genetic regulation of muscat flavor in grapevine and it also sheds light on the domestication history of Muscats. VvDXS appears to be a possible human-selected locus in grapevine domestication and post-domestication. The putative causal SNP identified in Muscat varieties as well as the unique mutations identifying the muscat-like aromatic mutants under study may be immediately applied in marker-assisted breeding programs aimed at enhancing fragrance and aroma complexity respectively in table grape and Wine Cultivars.
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A candidate gene association study on muscat flavor in grapevine (Vitis vinifera L.)
BMC Plant Biology, 2010Co-Authors: Francesco Emanuelli, Loic Le Cunff, Patrice This, Jean-michel Boursiquot, Laura Costantini, Juri Battilana, Maria S. GrandoAbstract:Background: The sweet, floral flavor typical of Muscat varieties (Muscats), due to high levels of monoterpenoids (geraniol, linalool and nerol), is highly distinct and has been greatly appreciated both in table grapes and in Wine since ancient times. Muscat flavor determination in grape (Vitis vinifera L.) has up to now been studied by evaluating monoterpenoid levels through QTL analysis. These studies have revealed co-localization of 1-deoxy-D-xylulose 5-phosphate synthase (VvDXS) with the major QTL positioned on chromosome 5. Results: We resequenced VvDXS in an ad hoc association population of 148 grape varieties, which included muscat-flavored, aromatic and neutral accessions as well as muscat-like aromatic mutants and non-aromatic offsprings of Muscats. Gene nucleotide diversity and intragenic linkage disequilibrium (LD) were evaluated. Structured association analysis revealed three SNPs in moderate LD to be significantly associated with muscat-flavored varieties. We identified a putative causal SNP responsible for a predicted non-neutral substitution and we discuss its possible implications for flavor metabolism. Network analysis revealed a major star-shaped cluster of reconstructed haplotypes unique to muscat-flavored varieties. Moreover, muscat-like aromatic mutants displayed unique non-synonymous mutations near the mutated site of Muscat genotypes. Conclusions: This study is a crucial step forward in understanding the genetic regulation of muscat flavor in grapevine and it also sheds light on the domestication history of Muscats. VvDXS appears to be a possible human-selected locus in grapevine domestication and post-domestication. The putative causal SNP identified in Muscat varieties as well as the unique mutations identifying the muscat-like aromatic mutants under study may be immediately applied in marker-assisted breeding programs aimed at enhancing fragrance and aroma complexity respectively in table grape and Wine Cultivars
