Comprehensive analysis of DUF761 genes identifies PdeCFE22 conferring enhanced drought tolerance in Populus deltoides

Drought stress severely constrains both wood production and quality in Populus species, which are of considerable ecological and industrial importance. Proteins containing the DUF761 domain, named the CFE gene family, have been implicated in abiotic stress. The systematic characterization of the CFE family and its functional roles, however, is still limited, particularly in Populus deltoides . Here, we identified 35 PdeCFE genes through a genome-wide scan in P. deltoides . Comprehensive analysis, including gene structure, genomic locations, and evolutionary relationships, revealed the key characteristics of the PdeCFE family. Analysis of the PdeCFEs promoter regions revealed a significant enrichment of cis -acting elements associated with plant hormones and abiotic stresses, with particular enrichment of ABA-responsive elements (ABREs). Expression patterns across various tissues and under osmotic stress were consistent with this finding. Co-expression network analysis highlighted PdeCFE22 as a hub gene with extensive connectivity, suggesting its central role in stress adaptation. Functional studies revealed that heterologous expression of PdeCFE22 in yeast enhanced osmotic resistance, while overexpression of PdeCFE22 in P. deltoides improved drought tolerance under different drought conditions by increasing ROS scavenging capacity and activating the ABA signaling pathway. Additionally, we demonstrated that PdeCFE22 physically interacts with PdeNAC062, a crucial ABA pathway transcription factor. Our comprehensive analysis of the P. deltoides CFE family identified PdeCFE22 as a positive regulator of drought tolerance, thereby establishing it as a prime target for molecular breeding of stress-resilient poplar varieties. • Thirty-five PdeCFE genes were identified and characterized in Populus deltoides . • PdeCFEs show tissue-specific and osmotic-induced expression. • PdeCFE22 -overexpressing enhances drought tolerance in Populus deltoides ‘Danhong’. • PdeCFE22 physically interacts with PdeNAC062.