NHX1 — Solanum lycopersicum

Summary

SlNHX1 (SOLYC10G006080.3) on tomato chromosome 10 encodes a sodium/hydrogen exchanger belonging to the NaH_exchanger and CPA1 cation/H_exchanger families, with lithium:proton and potassium:proton antiporter activity. The gene is associated with vacuolar membrane transport, sodium import and export, cell pH regulation, and ion homeostasis. In tomato, SlNHX1 has been linked to cadmium tolerance and alkaline stress tolerance, while related family members connect it to saline-alkali stress resistance and ionic balance. Broader associations include yield traits, lycopene content, photosynthetic rate, water use efficiency, and responses to high temperature and abiotic stress. The gene is also linked to stomatal conductance, drought tolerance, root growth, auxin homeostasis, and vacuolar pH regulation. Studies of related genes in other species further connect the family to sodium and potassium homeostasis, salt tolerance, and heat and cold stress tolerance.