Editing approaches to improve stress tolerance in tomato

High soil salinity and water deficit severely impact the growth and productivity of tomato (Solanum lycopersicum L.). To cope with these stress conditions, plants activate a complex network of interconnected pathways.
We aim to modify some of these pathways through genome editing.
The SALT OVERLY SENSITIVE (SOS) pathway regulates the activation of transporters to minimize the uptake of the toxic ion Na⁺ into plant cells and tissues during salt stress. SALT OVERLY SENSITIVE1 (SOS1), which encodes a Na⁺/H⁺ transporter located in the plasma-membrane, is a core component of the SOS pathway and a key determinant of salt tolerance in plants.
The cytosolic C-terminal tail of SOS1 contains an activation domain and an auto-inhibitory domain.
In the resting state, the SOS1 protein is inactive due to the interaction between the two domains.
Here, we used a genome editing approach to generate tomato lines carrying a constitutively active form of SOS1. Phenotyping of sos1 lines edited to generate deletions of the C-terminal region, including the auto-inhibitory domain, showed enhanced salt stress tolerance in vitro, such as increased seed germination and primary root elongation in seedlings under NaCl treatment.
These results contribute to the understanding of the functional role of the C-terminal tail of SOS1 in tomato.

International Symposium on Biotechnological Tools in Horticulture

P. Punzo, V. Cirillo, S. Esposito, A. Ruggiero, N. D’Agostino, S. Grillo, T. Cardi, A. Nicolia, G. Batelli

genome editing, CRISPR/Cas9, salt stress, SOS pathway, phenotyping

https://doi.org/10.17660/ActaHortic.2026.1454.10