Extracellular signal peptide that regulates cell fate. Represses root apical meristem maintenance. Inhibits irreversibly root growth by reducing cell division rates in the root apical meristem (PubMed:20697738). Regulates the transition of protophloem cells from proliferation to differentiation, thus impinging on postembryonic growth capacity of the root meristem; this signaling pathway requires CRN and CLV2 (PubMed:28607033). Mostly expressed in roots, seedlings, leaves, flowers, stems and apex, and, to a lower extent, in siliques and pollen. Expressed specifically in differentiating cells of the root. Belongs to the CLV3/ESR signal peptide family.