DOF transcription factor Dof5.1 influences leaf axial patterning by promoting Revoluta transcription in Arabidopsis

• Published in: The Plant journal : for cell and molecular biology Vol. 64; no. 3; pp. 524 - 535
• Main Authors: Kim, Hyung‐Sae, Kim, Sung Jin, Abbasi, Nazia, Bressan, Ray A, Yun, Dae‐Jin, Yoo, Sang‐Dong, Kwon, Suk‐Yun, Choi, Sang‐Bong
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.11.2010
• Subjects: activation tagging mutant; Arabidopsis; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Auxins; Binding sites; Biosynthesis; Botany; Chromatin; Dof transcription factor; Dof5.1; Electrophoretic mobility; Gene Expression Regulation, Plant; Homeodomain Proteins - genetics; Homeodomain Proteins - metabolism; Immunoprecipitation; Indoleacetic Acids - metabolism; leaf polarity; Leaves; Mutagenesis, Insertional; Mutation; Overexpression; Plant Leaves - growth & development; Plants, Genetically Modified - genetics; Plants, Genetically Modified - growth & development; Plants, Genetically Modified - metabolism; Polarity; Promoter Regions, Genetic; Promoters; Protein Interaction Domains and Motifs; Proteins; rev gene; Revoluta; Transcription; Transcription factors; Transcription Factors - genetics; Transcription Factors - metabolism; Transcription, Genetic; Zinc finger proteins
• ISSN: 0960-7412; 1365-313X
• DOI: 10.1111/j.1365-313x.2010.04346.x

Dof proteins are transcription factors that have a conserved single zinc finger DNA‐binding domain. In this study, we isolated an activation tagging mutant Dof5.1‐D exhibiting an upward‐curling leaf phenotype due to enhanced expression of the REV gene that is required for establishing adaxial-abaxial polarity. Dof5.1‐D plants also had reduced transcript levels for IAA6 and IAA19 genes, indicating an altered auxin biosynthesis in Dof5.1‐D. An electrophoretic mobility shift assay using the Dof5.1 DNA‐binding motif and the REV promoter region indicated that the DNA‐binding domain of Dof5.1 binds to a TAAAGT motif located in the 5′‐distal promoter region of the REV promoter. Further, transient and chromatin immunoprecipitation assays verified binding activity of the Dof5.1 DNA‐binding motif with the REV promoter. Consistent with binding assays, constitutive over‐expression of the Dof5.1 DNA‐binding domain in wild‐type plants caused a downward‐curling phenotype, whereas crossing Dof5.1‐D to a rev mutant reverted the upward‐curling phenotype of the Dof5.1‐D mutant leaf to the wild‐type. These results suggest that the Dof5.1 protein directly binds to the REV promoter and thereby regulates adaxial-abaxial polarity.