Analysis of WRKY Gene Family in Acer fabri and Their Expression Patterns Under Cold Stress

Background/Objectives: The WRKY gene family plays a critical role in plant stress responses; however, its function in Acer fabri (A. fabri) under cold stress conditions remains poorly understood. This study aims to identify WRKY genes in A. fabri, analyze their structural characteristics, and investigate their expression patterns under cold stress, thereby establishing a foundation for further exploration of their roles in cold stress responses. Methods: Using transcriptional data from A. fabri subjected to cold stress, we identified 46 WRKY family genes. We employed bioinformatics tools to conduct a comprehensive analysis of the physical and chemical properties of these genes, predict their subcellular localization, and construct a phylogenetic tree. A heatmap was generated to visualize the expression levels of WRKY genes across different treatment conditions. To validate our findings, qRT-PCR was performed on 10 highly expressed WRKY genes to analyze their temporal expression patterns during cold stress exposure. Results: The analysis revealed that WRKY genes in A. fabri are predominantly localized to the nucleus, with protein lengths ranging from 55 to 1027 amino acids. Notably, all WRKY genes possessed the conserved WRKYGQK domain. Under cold stress conditions, the WRKY gene expression exhibited a general trend of increasing followed by decreasing, with peak expression observed at 24 h post-treatment. qRT-PCR analysis corroborated this pattern for the selected genes. Conclusions: This study represents the first comprehensive structural and expression analysis of the A. fabri WRKY gene family under cold stress conditions. Our findings provide valuable insights into their potential roles in plant cold stress responses, and lay the groundwork for future investigations into the molecular mechanisms underlying WRKY-mediated cold stress tolerance in A. fabri.