Vitis vinifera cultivar:Prieto Picudo Transcriptome or Gene expression

The grapevine cultivar Prieto Picudo, traditional from Castilla y León, presents a somatic variant, Prieto Picudo Oval, with more elliptic berries. For decades viticulturists have shown interest in this variant and clones showing this phenotype have been selected. The aim of this thesis was to phenotypically characterize both morphotypes of Prieto Picudo and to determine the cellular and molecular causes of the differences and the developmental stage when they appear. An RNA-seq experiment allowed us to identify 52 genes differentially expressed between flowers of both morphotypes during the morphogenesis of the pistil. These genes include several regulators of gene expression over-expressed and sub-expressed in the oval variant that might be involved in the differential pistil development. Among them, the most over-expressed gene in the oval variant, annotated as a glutamate receptor, showed a single haplotype expressed in this variant and absence of expression in the normal variant. It might indicate that a mutation in one allele of this locus causes a deregulation of the gene in the oval variant. This work represents a breakthrough in the understanding of the developmental processes that produce changes in fruit shape in grapevine and it could provide a basis for the identification of the mutation responsible for the somatic variation between normal and oval variants of Prieto Picudo.