The Dof (DNA-binding with one finger) Cys2/Cys2-type zing finger is an around 50 amino acid motif found in plant transcription factors involved in the regulation of various processes. The arrangement of cysteines has some significant ressemblance to GATA (see <PDOC00300>) and steroid hormone receptor (see <PDOC00031>) zinc fingers [1]. Like other zinc fingers the Dof domain has a dual activity: it binds DNA in a sequence-specific manner with the core binding site formed by the AAAG sequence [1] and it can also mediates protein-protein interaction (see below).

Some of the proteins known to contain a Dof zinc finger are listed below:

• Maize ZmDof1 protein, an activator of various light-regulated genes.
• Pumpkin ascorbate oxidase promoter-binding protein (AOBP).
• Arabidopsis thaliana OBF binding protein 1 (OBP1). It interacts with the basic leucine zipper transcription factors OBF4 and OBF5 through its Dof zinc finger to enhance their DNA binding to OCS element sequences [2].
• Arabidopsis thaliana Dof affecting germination 1 protein (DAG1), a transcription factor specifically involved in the maternal control of seed germination.
• Tobacco NtBBF1 protein, a regulatory factor of the auxin-inducible rolB gene.
• Maize PBF1 protein, a transcription factor controlling endosperm specific expression of storage proteins.

The pattern we developed covers the whole zinc finger and the first eight amino acids of the conserved basic C-terminal tail essential for the DNA binding activity [3]. We also developed a profile that spans the whole domain.