Function
Negative regulator of cell proliferation in the adaxial side of leaves. Regulates the formation of a symmetric lamina and the establishment of venation. Positively regulates LATERAL ORGAN BOUNDARIES (LOB) within the shoot apex, and the class III HD-ZIP genes REV, PHB, and PHV. Interacts directly with ASYMMETRIC LEAVES 1 (AS1) to repress the knox homeobox genes KNAT1, KNAT2, and KNAT6 and the abaxial determinants ARF3, KAN2 and YAB5. May act in parallel with the RDR6-SGS3-AGO7 pathway, an endogenous RNA silencing pathway, to regulate the leaf morphogenesis (PubMed:11311158, PubMed:12787254, PubMed:12874130, PubMed:14508003, PubMed:16006579, PubMed:16699177, PubMed:17395603, PubMed:17559509). Required for the binding of AS1 to the KNOX genes (PubMed:23271976). Involved in leaf polarity establishment by functioning cooperatively with RH10 or RID2 to repress abaxial genes ARF3, ARF4, KAN1, KAN2, YAB1 and YAB5, and the knox homeobox genes KNAT1, KNAT2, KNAT6, and STM to promote adaxial development in leaf primordia at shoot apical meristems at high temperatures (PubMed:27334696).