From genes to vineyards: system biology and new breeding technologies for water stress tolerance in grapevines

Cis-acting regulatory elements are DNA sequences that can be bound by transcription factors to regulate the expression of genes in a condition-dependent and tissue-specific way. It is nowadays possible to search for DNA motives and sequences that a given transcription factor is binding or at least can, but it is still hard to have a glance at all the transcription factors that are contemporaneously located at the same locus. Inspired by an existing technique that uses the CRISPR-Cas system in mammal cells, we are trying to develop a protocol to study such regulation in Vitis vinifera. Using the highly sequence-specific binding capacity of a catalytically inactive Cas9 protein (dCas9), our idea is to set up a system to target a desired sequence and precipitate all the crosslinked proteins and distantly interacting chromatin at this locus and analyze them.

Bois noir (BN) is a cicada-transmitted grapevine disease that today causes up to 50% yield and vine loss in vineyards. It is caused by the phytoplasma Candidatus Phytoplasma solani (16SrXII-A).

Wine production is a complex biochemical process that involves a heterogeneous microbiota consisting of different microorganisms such as yeasts, bacteria, and filamentous fungi. Among these microorganisms, yeasts play a predominant role in the chemistry of wine, as they actively participate in alcoholic fermentation, a biochemical process that transforms the sugars in grapes into ethanol and carbon dioxide while producing additional by-products. The quality of the final product is greatly influenced by the microbiota present in the grape berry, and the demand for indigenous yeast starters adapted to specific grape must and reflecting the biodiversity of a particular region is increasing. This supports the concept that indigenous yeast strains can be associated with a “terroir”.

The Registered Appellation of Origin Mark (RAOM) « Jerez-Xérès-Sherry and Manzanilla Sanlucar de Barrameda » is one of the oldest and more important zone in wine history and production. «Albarizas» unit (white calcareous marls with sea-fossils) is the most representative geological material of the RAOM (75%) and even more in the central-NW area of the RAOM, known as «Jerez Superior» area (Superior Quality Sherry Area). « Albarizas » form undulated hillocks (3-10% slope) and hills (>10% slope), the litologic unit has E-W and S-W direction, and Regosols and Leptosols are the principal soils.

Background: The Flavan-3-ol extraction from grape skin and seed during red-winemaking and their retention into wines depend on many factors, some of which are modified in the winemaking of blend wines. Recent research shows that Marselan, have grapes with high proportion of skins with high concentrations of flavanols, but produces red-wines with low proportion of skin derived flavanols, differently to the observed in Syrah or Tannat. But the factors explaining these differences are not yet understood.