NHX1 — Brassica juncea

Summary

BJUA09G66950S (BjNHX1) on Indian mustard chromosome A09 encodes a sodium/hydrogen exchanger belonging to the NaH_exchanger and cation/H_exchanger_CPA1 families, with potassium:proton antiporter, sodium transporter and sodium:hydrogen exchanger activities, and is associated with protein binding. The gene is linked to vacuolar membrane, vacuole and plant-type vacuole localisation, and is associated with processes including sodium import, vacuolar membrane transport, cell pH regulation, photoprotection, detoxification, calcium signaling, regulation of stomatal closure, chlorophyll fluorescence, response to stress, activation of salinity response, leaf development, and homeostasis. Associations with traits include photosynthetic rate, chlorophyll content, and salt tolerance (SALTTL), and with phenotypes such as hypocotyl elongation, sodium ion transport, plant growth, cell expansion, flower development, vacuolar pH, potassium homeostasis, root growth, stem internode length, auxin homeostasis, nitrogen assimilation, fiber yield, photosynthetic performance, stomatal regulation, gravitropism, apical dominance, and salinity tolerance. Studies of related genes in other species link the family to salt tolerance, potassium uptake, Na+/H+ transport activity, pH homeostasis, heat tolerance, seed germination, cold tolerance, biomass production, and disease resistance.