Genome-wide characterization of the SiDof gene family in foxtail millet (Setaria italica)

- The present study identified 35 Dof transcription factor-encoding genes in the S. italica genome.
- A phylogenetic tree was constructed and the Dof genes were classified into six major groups.
- Expression profiling of SiDofs in response to stress suggested that SiDof 7 and SiDof 15 are involved in drought stress signalling.

Dof (DNA binding with one finger) proteins, which constitute a class of transcription factors found exclusively in plants, are involved in numerous physiological and biochemical reactions affecting growth and development. A genome-wide analysis of SiDof genes was performed in this study. Thirty five SiDof genes were identified and those genes were unevenly distributed across nine chromosomes in the Seteria italica genome. Protein lengths, molecular weights, and theoretical isoelectric points of SiDofs all vary greatly. Gene structure analysis demonstrated that most SiDof genes lack introns. Phylogenetic analysis of SiDof proteins and Dof proteins from Arabidopsis thaliana, rice, sorghum, and Setaria viridis revealed six major groups. Analysis of RNA-Seq data indicated that SiDof gene expression levels varied across roots, stems, leaves, and spike. In addition, expression profiling of SiDof genes in response to stress suggested that SiDof 7 and SiDof 15 are involved in drought stress signalling. Overall, this study could provide novel information on SiDofs for further investigation in foxtail millet.

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