Promotes cellular proliferation and expansion (PubMed:17989228). Induces outward H(+) fluxes in roots (PubMed:25267325). Expressed in roots, stems, leaves, flowers and shoot apical meristems. By wounding. Glycosylated with 3 L-arabinose units. The sulfation and the L-Ara(3) chain are required for full activity. Belongs to the sulfated-peptide plant hormone family.