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IVES 9 IVES Conference Series 9 Open-GPB 9 Open-GPB-2024 9 Flash - New biotechnological tools 9 Enhancing hydric stress tolerance by editing the VviMYB60 promoter with CRISPR/Cas9 

Enhancing hydric stress tolerance by editing the VviMYB60 promoter with CRISPR/Cas9 

Abstract

Climate change presents increasing challenges to viticulture, particularly with rising water stress contributing significantly to yield losses and damages. The identification of the MYB60 transcription factor, which regulates stomatal opening and closing in Arabidopsis thaliana and Vitis vinifera, offers potential solutions. Notably, knockout studies in Arabidopsis have shown reduced stomatal opening and increased drought tolerance in myb60 mutants. Additionally, the grapevine ortholog, VviMYB60, can restore the wild-type phenotype of Arabidopsis myb60 mutants. Further investigation of the Arabidopsis promoter region has revealed that mutations in DOF motifs lead to reduced expression of AtMYB60.

Utilizing the advancements in CRISPR/Cas9 genome editing, this project aims to modify the VviMYB60 promoter region to lower gene expression, thereby reducing stomatal opening in grapevines. Binary vectors for genome editing were constructed to target two specific regions of the VviMYB60 promoter. Agrobacterium-mediated transformation was performed on Chardonnay embryogenic calli, resulting in the successful regeneration of plants under selection conditions. Sanger sequencing analysis of the targeted region confirmed the occurrence of genetic edits in four of the six lines analyzed so far.

To further characterize the edited lines, next-generation sequencing will be utilized, providing a more comprehensive understanding of the mutations, as well as gene expression of VviMYB60 will be evaluated to confirm that the editing reduces its expression. Morphological and physiological parameters will be measured after acclimatation in greenhouse and finally these edited lines will undergo drought tolerance testing to assess their performance.

DOI:

Publication date: June 13, 2024

Issue: Open GPB 2024

Type: Article

Authors

Manuela Campa1*, Loredana Moffa2, Luca Nerva2, Walter Chitarra2, Johan Burger1

1 Genetics Department, Faculty of Agrisciences, Stellenbosch University, 7600 Stellenbosch, South Africa
2 Research Centre for Viticulture and Enology, Council for Agricultural Research and Economics (CREA-VE), Via XXVIII Aprile 26, 31015 Conegliano (Italy)

Contact the author*

Keywords

CRISPR/Cas9, VviMYB60, promoter, drought tolerance, stomatal regulation

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

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