NHX1 — Nicotiana attenuata

Summary

A4A49_08345 (NHX1/NHX2) on coyote tobacco chromosome 6 encodes a sodium/hydrogen exchanger belonging to the CPA1 cation/H⁺ exchanger family, with annotated lithium:proton antiporter, potassium:proton antiporter, sodium transporter, NAD ADP-ribosyltransferase, protein kinase and protein binding activities. The gene is associated with vacuolar membrane transport, sodium and potassium ion import and homeostasis, cell pH regulation, nitric oxide anabolism, and responses to superoxide. It localises to the tonoplast, vacuole, endosome, retromer complex, chloroplast envelope and plastid. Associations include leaf potassium content, sodium uptake, yield, photosynthetic rate, stomatal resistance, transpiration, root development, plant height, abscisic acid sensitivity, disease tolerance, and responses to high temperature and UV-B light. Studies of related genes in other species link the gene to drought tolerance, sodium tolerance, stomatal regulation, auxin homeostasis, gravitropism, cell expansion, and seed storage protein processing.