title: Molecular, genetic and transcriptional evidence for a role of VvAGL11 in stenospermocarpic seedlessness in grapevine.
abstract: BACKGROUND
  Stenospermocarpy is a mechanism through which certain genotypes of Vitis vinifera L. such as Sultanina produce berries with seeds reduced in size. Stenospermocarpy has not yet been characterized at the molecular level.
  
  
  RESULTS
  Genetic and physical maps were integrated with the public genomic sequence of Vitis vinifera L. to improve QTL analysis for seedlessness and berry size in experimental progeny derived from a cross of two seedless genotypes. Major QTLs co-positioning for both traits on chromosome 18 defined a 92-kb confidence interval. Functional information from model species including Vitis suggested that VvAGL11, included in this confidence interval, might be the main positional candidate gene responsible for seed and berry development.Characterization of VvAGL11 at the sequence level in the experimental progeny identified several SNPs and INDELs in both regulatory and coding regions. In association analyses performed over three seasons, these SNPs and INDELs explained up to 78% and 44% of the phenotypic variation in seed and berry weight, respectively. Moreover, genetic experiments indicated that the regulatory region has a larger effect on the phenotype than the coding region. Transcriptional analysis lent additional support to the putative role of VvAGL11's regulatory region, as its expression is abolished in seedless genotypes at key stages of seed development. These results transform VvAGL11 into a functional candidate gene for further analyses based on genetic transformation.For breeding purposes, intragenic markers were tested individually for marker assisted selection, and the best markers were those closest to the transcription start site.
  
  
  CONCLUSIONS
  We propose that VvAGL11 is the major functional candidate gene for seedlessness, and we provide experimental evidence suggesting that the seedless phenotype might be caused by variations in its promoter region. Current knowledge of the function of its orthologous genes, its expression profile in Vitis varieties and the strong association between its sequence variation and the degree of seedlessness together indicate that the D-lineage MADS-box gene VvAGL11 corresponds to the Seed Development Inhibitor locus described earlier as a major locus for seedlessness. These results provide new hypotheses for further investigations of the molecular mechanisms involved in seed and berry development.
authors: Biotechnology Unit, La Platina Experimental Station, INIA, Avenida Santa Rosa 11610, Santiago, Chile. nmejia@inia.cl
authors: Nilo
authors: N
authors: Mejía
authors: Braulio
authors: B
authors: Soto
authors: Marcos
authors: M
authors: Guerrero
authors: Ximena
authors: X
authors: Casanueva
authors: Cléa
authors: C
authors: Houel
authors: María de Los Ángeles
authors: Mde L
authors: Miccono
authors: Rodrigo
authors: R
authors: Ramos
authors: Loïc
authors: L
authors: Le Cunff
authors: Jean-Michel
authors: JM
authors: Boursiquot
authors: Patricio
authors: P
authors: Hinrichsen
authors: Anne-Françoise
authors: AF
authors: Adam-Blondon
mesh_terms: D000595:Amino Acid Sequence; D002874:Chromosome Mapping; D018506:Gene Expression Regulation, Plant; D026161:MADS Domain Proteins / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D040641:Quantitative Trait Loci; D012639:Seeds / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D016415:Sequence Alignment; D014158:Transcription, Genetic; D027843:Vitis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism
chemical_list: D026161:MADS Domain Proteins; D010940:Plant Proteins