CRISPR-Cas9 gene editing of the Sal1 gene family in wheat

Authors: Mohr, Toni; Horstman, James; Gu, Yong; ELARABI, NAGWA - Cairo University; ABDALLAH, NAGLAA - Cairo University; Thilmony, Roger

Submitted to: Plants
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/26/2022
Publication Date: 8/20/2022
Citation: Mohr, T.J., Horstman, J.D., Gu, Y.Q., Elarabi, N.I., Abdallah, N.A., Thilmony, R.L. 2022. CRISPR-Cas9 gene editing of the Sal1 gene family in wheat. Plants. 11(17). Article 2259. https://doi.org/10.3390/plants11172259.
DOI: https://doi.org/10.3390/plants11172259

Interpretive Summary: Environmental stresses like drought limit crop production worldwide. Work in model plants systems had identified a Sal1 gene that when inactivated, made the plants more tolerant of water limiting environmental conditions. Research was conducted using precise gene editing techniques to modify the function of the Sal1 gene family in bread wheat to test if the modified plants could better tolerate drought. Wheat plants were genetically engineered to express the gene editing components. Characterization of these plants identified several that carried the desired targeted mutations with the six Sal1 genes present in the genome. Although these modified plants did stay green longer under drought conditions, the plants did not yield more than unmodified wheat plants. Some of the mutants also had thinner stems and lower yield than unmodified plants in well-watered conditions. These mutant plants generated from this research will be potentially useful in further research studying the function of this gene family in wheat.

Technical Abstract: The highly conserved Sal1 encodes a bifunctional enzyme with inositol polyphosphate-1-phosphatase and 3' (2'), 5'-bisphosphate nucleotidase activity and has been shown to alter abiotic stress tolerance in plants when disrupted. Precise gene editing techniques were used to generate sal1 mutants in hexaploid bread wheat. The CRISPR (Clustered Regulatory Interspaced Short Palindromic Repeats) Cas9 system with three guide RNAs (gRNAs) was used to inactivate six Sal1 homologous genes within the Bobwhite wheat genome. The resulting mutant wheat plants with all their Sal1 genes disabled, had slimmer stems, had a modest reduction in biomass and senesced more slowly in water limiting conditions, but did not exhibit improved yield under drought conditions. Our results show that multiplexed gRNAs enabled effective targeted gene editing of the Sal1 gene family in hexaploid wheat. These sal1 mutant wheat plants will be a resource for further research studying the function of this gene family in wheat.