Transcription regulator involved in gene regulation during late embryogenesis. Its expression to the epidermis is sufficient to control foliar organ identity by regulating positively the synthesis abscisic acid (ABA) and negatively gibberellin production. Negatively regulates TTG1 in the embryo. Positively regulates the abundance of the ABI3 protein in the seed. Cooperates with KIN10 to regulate developmental phase transitions and lateral organ development and act both as positive regulators of abscisic acid (ABA) signaling during germination (PubMed:22026387, PubMed:22902692). Phosphorylation by KIN10 is required to positively regulates embryogenesis, seed yield, and plant growth at high temperature. Interacts with KIN10. Expressed in cotyledons and hypocotyls. Expressed in developing embryo. At globular stage, expressed in all cells of the embryo proper. At heart stage, preferentially expressed in the protodermal tissue. In mature embryo, expressed in the provascular tissue, root cap and mature epidermis. Expressed in the aleurone layer in mature seed. Expressed in leaf primordia and shoot apical meristem (PubMed:22026387). Phosphorylation by KIN10 increases its stability. Phosphorylated at one or more of the Ser-55, Ser-56 and/or Ser-57 residues. Accumulation of anthocyanins in embryo. Presence of trichomes on cotyledons. Unusual pattern of storage product accumulation in embryos and cotyledons.