terclim by ICS banner
IVES 9 IVES Conference Series 9 Open-GPB 9 Open-GPB-2024 9 Flash - New biotechnological tools 9 Deciphering the function and regulation of VviEPFL9 paralogs to modulate stomatal density in grapevine through New Genomic Techniques

Deciphering the function and regulation of VviEPFL9 paralogs to modulate stomatal density in grapevine through New Genomic Techniques

Abstract

Stomata are microscopic pores mainly located in leaf epidermis, allowing gas exchanges between plants and atmosphere. Stomatal initiation relies on the transcription factor SPEECHLESS which is mainly regulated by the MAP kinase cascade, in turn controlled by small signaling peptides, the Epidermal Patterning Factors (EPF and EPF-Like), namely EPF1, EPF2 and EPFL9. While EPF1 and EPF2 induce the inhibition of SPEECHLESS, their antagonist, EPFL9, stabilizes it, leading to stomatal formation. In grapevine, there are two paralogs for EPFL9, VviEPFL9-1 and VviEPFL9-2. Despite their structural similarity, it remains unclear whether they are differentially regulated and have distinct roles. In our study we showed that while VviEPFL9-1 is expressed only in the apex, VviEPFL9-2 is expressed both in the apex and in mature leaves along the plant axis and is significantly repressed by ABA. To support experimental data, an in-silico transcriptomic analysis has been carried out using publicly available datasets. In addition, both genes were functionally characterized using knock-out (KO) mutants generated via CRISPR/Cas9. Leaf stomatal density and gas exchange parameters were significantly different between ‘Sugraone’ WT plants and VviEPFL9-2 KO lines, whereas the differences were negligible between WT and VviEPFL9-1 KO lines. Moreover, a water stress experiment was carried out to deeply compare the physiology of edited lines and WT plants under drought conditions. Our results suggest that VviEPFL9 paralogs have distinct roles in determining stomatal plasticity during leaf growth, and that VviEPFL9-2 may be considered a key target to increase grapevine resilience to water deficiency.

DOI:

Publication date: June 13, 2024

Issue: Open GPB 2024

Type: Article

Authors

Umar Shahbaz1,2, Pierre Videau3, Katerina Labonova3, David Navarro-Payá4, Alvaro Vidal1,2, José Tomás Matus4, Mickael Malnoy1, Olivier Zekri3, Fabio Fiorani5, Michele Faralli2, Lorenza Dalla Costa1*

1 Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige, Italy
2 Center Agriculture Food Environment (C3A), University of Trento, 38098, San Michele all’Adige, Italy
3 Novatech, Mercier Groupe, Le Champ des Noels, France
4 Institute for Integrative Systems Biology, Universitat de València-CSIC,46980 Paterna, Valencia, Spain
5 Institute of Bio- and Geo-Sciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany

Contact the author*

Keywords

Vitis vinifera, Epidermal Patterning Factors, CRISPR/Cas9, gas exchange, water stress

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

Related articles…

Effects of different organic amendments on soil, vine, grape and wine, in a long-term field experiment in Chinon vineyard (France)

In a long-term experiment carried out in Chinon vineyard (37, France) during 23 years, the effects of several organic amendments were studied on soil, vine, grapes and wine. Four main treatments were compared on a calcareous sandy soil: control without organic amendment, dry crushed pruning wood at 2.1.t-1.ha-1.year-1 (D1), cow manure at 10 t-1. ha-1.year-1 (D1) and cow manure applied at 20 t-1.ha-1.year-1 (D2). D1 levels were calculated to fill the annual humus losses by mineralization.

Modulation of berry composition by different vineyard management practices

High concentration of sugars in grapes and alcohol in wines is one of the consequences of climate change on viticulture production in several wine-growing regions. In order to investigate the possibilities of adaptation of vineyard management practices aimed to reduce the accumulation of sugar during the maturation phase without reducing the accumulation of anthocyanins in grapes, a study with severe shoot trimming, shoot thinning, cluster thinning and date of harvest was conducted on Merlot variety in Istria region (Croatia), under the Mediterranean climate. Four factors which may affect grape maturation and its composition at harvest were investigated in a two-years experiment; severe shoot trimming applied at veraison when >80% of berries changed colour (in comparison to untreated control), shoot thinning (0 and 30%), cluster thinning (0 and 30%), and the date of harvest (early and standard harvest dates). Shoot thinning had no significant impact on berry composition, despite the obtained reduction in yield per vine. Lower Brix in grapes were obtained with earlier harvest date and if no cluster thinning was applied, although at the same time a reduction in the concentration of anthocyanins in berries was observed in these treatments. On the other hand, if severe shoot trimming was applied when >80% of berries changed colour, a reduction of Brix was obtained without a negative impact on berry anthocyanins concentration. We conclude that in cases when undesirably high sugar concentrations at harvest are expected, severe shoot trimming at 80% veraison may effectively be used in order to obtain moderate sugar concentration in berries together with the adequate phenolic composition.

Monitoring of microbial biomass to characterise vineyard soils

Le sol est un facteur important permettant la croissance de la vigne. Les propriétés physiques et chimiques, mais aussi microbiologiques ont une influence sur beaucoup des fonctions du sol comme la structure, le drainage, la fertilité, déterminant la vigueur des plantes et le potentiel œnologique des raisins.

CHARACTERIZATION OF THE VOLATILE COMPOUNDS PROFILE OF COMMERCIAL GRAPPAS OBTAINED FROM THE POMACE OF AMARONE WINES

Grappa is a traditional Italian alcoholic beverage, with an alcohol content generally between 40-60% vol., obtained from the distillation of grape pomace used for the production of wine. Grappa are often aged in wooden barrels. There are various types of grappa: young, aromatic, aged, extra-aged depending on whether the distillate comes from aromatic vines or is aged in wooden barrels for shorter or longer periods. There is also flavored grappa if herbs, fruit or roots are added. All this makes it an extremely heterogeneous product both from an organoleptic and compositional point of view.

Late pruning, an alternative for rainfed vine varieties facing new climatic conditions

In Chile there is a dry farming area known as a traditional wine region, where varieties brought by the Spanish conquerors still persist. These varieties, in general, are cultivated under traditional systems, with low use of technical and economic resources, and low profitability for their grapes and wines. In this region, as in other wine grape growing areas, climatic conditions have changed significantly in recent decades. In particular, the occurrence of spring frosts, when bud break has already begun, have generated significant losses for these growers.