NHX1 — Brassica juncea

Summary

BjNHX2 (gene symbol NHX1, BJUUNNG04140S) in Indian mustard (Brassica juncea) encodes a member of the cation/H⁺ exchanger CPA1 family, with potassium:proton antiporter activity, sodium transporter activity and sodium:hydrogen exchanger activity. It is associated with vacuolar membrane transport, sodium import, potassium ion import across the plasma membrane, cell pH regulation, photoprotection, detoxification, calcium signaling, regulation of stomatal closure, chlorophyll fluorescence, stress response, homeostasis and activation of salinity response. The gene is linked to chlorophyll content, plant growth, stomatal closure, transpiration, auxin homeostasis, cell expansion, hypocotyl elongation, flower development, potassium ion homeostasis, microtubule organization, root growth directionality, gravitropism and vacuolar pH. It localises to the vacuolar membrane, mitochondria, cytosol and plasmalemma. Related genes in other species link the family to salt tolerance and vacuolar pH regulation.