Genome-Wide Identification and Expression Profile Analysis of the NF-Y Transcription Factor Gene Family in Eucalyptus grandis

The nuclear factor Y (NF-Y) transcription factor family identified in plant organisms consists of NF-YA, NF-YB, and NF-YC subunits, known for their pivotal role in regulating plant growth, development, and responses to environmental stress. Despite extensive studies on the NF-Y gene family across various species, the understanding of the NF-Y gene family in Eucalyptus is incomplete. This study aimed to identify 31 EgrNF-Y genes (7 EgrNF-YA, 16 EgrNF-YB, and 8 EgrNF-YC) in Eucalyptus grandis, all displaying conserved core regions. The chromosome distribution analysis showed that these genes were unevenly distributed on 11 chromosomes. The protein interaction analysis revealed EgrNF-YA1/A4/A6 as central within the EgrNF-Y protein network, interacting extensively with other EgrNF-Y proteins. Prediction of promoter cis-elements suggested that the expression of EgrNF-Y genes may be affected by various hormonal and abiotic stresses. Tissue-specific expression patterns indicated the widespread presence of all 30 EgrNF-Y genes across different tissues. EgrNF-YB1 and EgrNF-YB11 are implicated in regulating E. grandis flowering, whereas the upregulated expression of EgrNF-YB6/B11/B13 under phosphorus deficiency is involved in phosphorus absorption and utilization. This study lays a foundation for further understanding of the evolutionary diversity of the NF-Y gene family and serves as a reference for future studies in woody plants.