Plays a role in meristem function. Contributes to the shoot apical meristem (SAM) maintenance and organ separation by controlling boundary establishment in embryo in a CUC1, CUC2 and STM-dependent manner. Involved in maintaining cells in an undifferentiated, meristematic state. Probably binds to the DNA sequence 5'-TGAC-3'. May form heterodimeric complex with the TALE/BELL protein BLH9/PNY. Interacts with OFP2 and OFP4. Expressed predominantly in shoot apices of seedlings, and, to a lower extent, in rosette leaves. First detected in torpedo stage embryos at the boundaries between the presumptive SAM and the cotyledons. Later expressed between the cotyledons and the meristem, and between the cotyledons. In seedlings, localized in stipules and at the boundaries between the SAM and the emerging primordia. Expressed at the site of lateral roots. Seems to be repressed by AS2 and AS1 but induced by STM, CUC1 and CUC2. Belongs to the TALE/KNOX homeobox family. It is uncertain whether Met-1 or Met-4 is the initiator. Truncated N-terminus. Truncated N-terminus.