Identification and Characterization of the DOF Gene Family in Phoebe bournei and Its Role in Abiotic Stress—Drought, Heat and Light Stress

<i>Phoebe bournei</i> is a second-class endangered and protected species unique to China, and it holds significant ecological and economic value. DNA binding one zinc finger (Dof) transcription factors are plant-specific regulators. Numerous studies have demonstrated that <i>Dof</i> genes are involved in plant growth, development and responses to abiotic stress. In this study, we identified and analyzed 34 <i>PbDof</i> gene members at the whole-genome level. The results indicated that the 34 <i>PbDof</i> genes were unevenly distributed across 12 chromosomes. We utilized the <i>Dof</i> genes from <i>Arabidopsis thaliana</i> and <i>P. bournei</i> to construct a phylogenetic tree and categorized these genes into eight subgroups. In the collinearity analysis, there were 16 homologous gene pairs between <i>AtDof</i> and <i>PbDof</i> and nine homologous gene pairs between <i>ZmDof</i> and <i>PbDof</i>. We conducted a <i>cis</i>-acting element analysis and found that <i>cis</i>-acting elements involved in light response were the most abundant in <i>PbDof</i> genes. Through SSR site prediction, we analyzed that the evolution level of <i>Dof</i> genes is low. Additionally, we assessed the expression profiles of eight <i>PbDof</i> genes under high temperature, drought, and light stress using qRT-PCR. In particular, <i>PbDof08</i> and <i>PbDof16</i> are significantly upregulated under the three stresses. This study provides foundational information for <i>PbDof</i> genes and offers new insights for further research on the mechanism of Dof transcription factors responding to stress, as well as the adaptation of <i>P. bournei</i> to environmental changes.