Essential transporter for growth and development under abiotic stress (PubMed:22996334). Mediates shoot branching by promoting the outgrowth of lateral shoots (PubMed:19140940). Required for salt tolerance via Na/K homeostasis, at least partly by regulating SKC1/OsHKT1;5 (PubMed:24908511). Necessary for hypodermal suberization of roots, which contributes to formation of the apoplastic barrier (PubMed:25041515). Expressed in the crown root primordia, endodermis, pericycle and stele in the root, in leaf primordia of main and axillary shoots, and in the vascular cells and leaf epidermis of older leaves. Strongly up-regulated in roots after exposure to salt and osmotic stresses (PubMed:24908511). Induced in roots by benzylaminopurine (BAP), abscisic acid (ABA) and salicylic acid (SA) (PubMed:22996334). Accumulates in shoots upon heat (e.g. 42 degrees Celsius) (PubMed:22996334). Repressed in roots by NaCl, jasmonic acid (JA), gibberellic acid (GA) and auxin (IAA) (PubMed:22996334). Accumulates in most hypodermal and some endodermal roots cells under stagnant deoxygenated conditions leading to hypoxia (PubMed:25041515). Belongs to the ABC transporter superfamily. ABCG family. Eye pigment precursor importer (TC 3.A.1.204) subfamily.