Acts as an important factor for cell fate determination and maintenance throughout plant development. Required for the organization of the root apical meristem (RAM) and the shoot apical meristem (SAM). Required to maintain genome stability and cell division activity in meristematic cells. Expressed in root tips, the shoot apical meristem (SAM), leaves, mature flowers and embryos. Strong developmental phenotypes, such as extremely short, and agravitropic primary roots, small aerial organ size, altered shape and pale white leaves, bushy inflorescence and reduced number of seeds.