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The DELLA protein RGA-LIKE2 (RGL2) is a key transcriptional repressor of gibberellic acid (GA) signaling that regulates seed germination. We identified GATA12 , a gene encoding a GATA-type zinc finger transcription factor, as one of the downstream targets of RGL2 in Arabidopsis thaliana . Our data show that freshly harvested (unstratified) seeds of GATA12 antisense suppression lines have reduced dormancy compared with the wild-type, while ectopic expression lines show enhanced seed dormancy. We show that GATA12 expression is negatively regulated by GA, and its transcript levels decline dramatically under dormancy-breaking conditions such as dry storage and cold stratification of seeds. GATA12 promoter has several GAMYB- and DOF-associated motifs that are known to be GA- and RGL2-responsive, respectively. Chromatin immunoprecipitation assay showed that a protein complex containing RGL2 can bind to GATA12 promoter and thereby regulate its expression. RGL2 lacks a DNA binding domain and requires a transcription factor to induce GATA12 expression. Our data show that this RGL2-containing protein complex includes DNA BINDING1 ZINC FINGER6 (DOF6), which is a known negative regulator of germination in freshly harvested seeds. We further show that this novel RGL2–DOF6 complex is required for activating GATA12 expression, thus revealing a molecular mechanism to enforce primary seed dormancy. [ABSTRACT FROM AUTHOR]