Probable transcription factor required for axillary (lateral) shoot meristem formation during vegetative development. Seems to act upstream of REVOLUTA. Expressed in roots and flowers. Expressed in the axils of leaf primordia and leaves from P1 to P20/22. In the axil of P1, expressed in 3 to 5 cell layers including the L1 to L3 layers of the shoot apical meristem (SAM). Then, extends from 1 or 2 cell layers in the adaxial-abaxial dimension. From P5 to P22, expression is restricted to a 1 to 2 cell-layer domain located within primordium. In the axils of older leaf primordia, expression decreases until it is no longer detectable in the axils of primordia older than P20/P22. Plants fail to initiate axillary meristems and do not form lateral shoots during vegetative development. Belongs to the GRAS family.