terclim by ICS banner
IVES 9 IVES Conference Series 9 Functional characterization of grapevine MLO genes to define their roles in Powdery mildew susceptibility by CRISPR/Cas9 genome editing

Functional characterization of grapevine MLO genes to define their roles in Powdery mildew susceptibility by CRISPR/Cas9 genome editing

Abstract

Successful powdery mildew (PM) infection in plants relies on Mildew Resistance Locus O (MLO) genes, which encode susceptibility factors essential for fungal penetration. In Arabidopsis, loss-of-function mutations in three clade-V MLOs, AtMLO2, 6, and 12 confer complete resistance to PM infection. Since then, efforts are on to discover MLO genes contributing to PM susceptibility in many species to introduce mlo-based PM-resistance. Earlier studies in tomato and grapevine, using the RNAi approach, attributed PM susceptibility to SlMLO1, 5, and 8 and VvMLO3, 13, and 17, respectively indicating likely functional redundancy among MLOs. Here, we disrupted the closest grapevine orthologues, VvMLO3, 4, 13, and 17 through CRISPR/Cas9-mediated mutagenesis in the microvine model with the goal of identifying the candidate MLO genes to introduce mlo-based PM resistance. Individual mutants mlo3, mlo4, mlo13 and mlo17 showed 8 to 50% less infection to E. necator, whereas double mutants, mlo3/4, mlo3/13 andmlo13/17 and triple mutant mlo3/13/17 showed 60 to 90% less infection. But the quadruple mlo3/4/13/17 mutant plants showed near complete PM resistance. Considerable differences were observed in the resistance level of clones among the triple and quadruple mutants due to the differences in editing efficiency of individual guide RNAs. Some mutants showed pleiotropic effects in the growth and development, ranging from early senescence and stunted growth to non-flowering phenotypes, which also seemed to depend on the percentage of gene-edited cells in the plant. The overarching goal is to excise the genome-integrated T-DNA cassette from the mutants using CRISPR Ribonucleoproteins for transgene-free PM resistance.

Download the abstract

DOI:

Publication date: June 13, 2024

Issue: Open GPB 2024

Type: Article

Authors

Satyanarayana Gouthu1*, Laurent Deluc2,3, Samuel Talbot1

1,2 Department of Horticulture, Oregon State University, Corvallis, OR, USA
3 Oregon Wine Research Institute, Oregon State University, Corvallis, OR, USA

Contact the author*

 

Keywords

Powdery mildew, Grapevine MLO, mildew-resistance, Gene Editing

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

Related articles…

Developmental stage-specific effects of high temperature on aroma accumulation in ‘Marselan’ grapes from the Helan Mountain region

The aroma of wine grapes is influenced by a complex metabolic network, with terroir factors, especially high temperatures, playing a critical role during berry development.

Read More

From geomorphological analysis to terroirs geo-pedological zonation: the Madiran and Pacherenc of Vic-Bilh A.O.C. as case of study

L’aire des A.O.C. Madiran et Pacherenc du Vic-Bilh est située sur le piémont nord-occidental des Pyrénées, au nord du cône de Ger.

Read More

Microclimatic differences in fruit zone of vineyards on different elevations of ‘nagy-eged hill’ in eger wine region, Hungary

The Bull’s Blood of Eger (‘Egri Bikavér’) is one of the most reputed red wines in Hungary and abroad, produced in the Northeastern part of the country.

Read More

Time stability of visitors’ preferences for preserving the worldwide cultural landscape alto douro wine region

The Alto Douro Wine Region (ADWR) was classified a world heritage site, specifically as a cultural landscape, by UNESCO, in 2001. The well known “Porto Wine” and other high quality wines are produced in the Douro region. As an attraction and touristic site, the cultural site has to meet the needs of more demanding visitors and to compete with a growing number of cultural sites, also classified by UNESCO. To achieve this goal, landscape managers and public authorities have much to profit from knowing and understanding visitors’ preferences regarding the attributes associated to its outstanding universal value.

Read More

Flavanol glycosides in grapes and wines : the key missing molecular intermediates in condensed tannin biosynthesis ?

Polyphenols are present in a wide variety of plants and foods such as tea, cacao and grape1. An important sub-class of these compounds is the flavanols present in grapes and wines as monomers (e.g (+)-catechin or (-)-epicatechin), or polymers also called condensed tannins or proanthocyanidins. They have important antioxidant properties2 but their biosynthesis remains partly unknown. Some recent studies have focused on the role of glycosylated intermediates that are involved in the transport of the monomers and may serve as precursors in the polymerization mechanism3, 4. The global objective of this work is to identify flavanol glycosides in grapes or wines, describe their structure and determine their abundance during grape development and in wine.

Read More