Transcriptional activator that specifically binds 5'-GATA-3' or 5'-GAT-3' motifs within gene promoters. May be involved in the regulation of some light-responsive genes (By similarity). Transcription activator involved in xylem formation. Functions upstream of NAC030/VND7, a master switch of xylem vessel differentiation (PubMed:25265867). Expressed in the vascular cylinder of roots. Expressed in the differentiation zone of the root stele. Overexpression of GATA12 induces the formation of ectopic xylem vessel-like elements. Belongs to the type IV zinc-finger family. Class A subfamily. Sequencing errors.