NHX1 — Brassica napus

Summary

BnNHX1 (DARMORV10_C09P05570.1) on chromosome C09 of oilseed rape encodes a sodium/hydrogen exchanger belonging to the NaH_exchanger and CPA1 cation/H+ exchanger families, with potassium:proton antiporter, sodium transporter and sodium:hydrogen exchanger activities. The gene is associated with vacuolar membrane localisation and linked to sodium and potassium ion membrane transport, vacuolar pH regulation, cell pH regulation, photoprotection, chlorophyll fluorescence, regulation of stomatal closure, and hypersensitivity. Associations include leaf relative water content, photosynthetic rate, chlorophyll content, and salinity tolerance (SALTTL). The gene has been connected to hypocotyl elongation, cell expansion, flower development, root growth directionality, stem internode length, auxin homeostasis, nitrogen assimilation, fiber yield, and gravitropism. Studies of related genes in other species link the family to salt tolerance, ion homeostasis, heat and cold tolerance, seed germination, biomass production, and disease resistance.