Transcription factor required for the asymmetric cell division involved in radial pattern formation in roots. Essential for both cell division and cell specification. Interacts with SCR1 (PubMed:17446396). Interacts with SMOS1 (PubMed:28069545). Expressed in leaves and roots. Detected in the stele, the endodermis and part of the cortex. In P3 leaf primordium, expressed ubiquitously in the L1 layer and in the inner cells at lower levels. Not limited to the developing stomata until the last cell divisions. Belongs to the GRAS family.