Genome-Wide Identification and Expression Analysis of Salt Tolerance-Associated WRKY Family Genes in Cyclocarya paliurus

WRKY proteins are key transcription factors involved in a range of physiological processes and environmental adaptations. Yet, little is known about the role WRKY genes play in Cyclocarya paliurus (Batal.) Iljinskaja (C. paliurus) a significant medicinal plant belonging to the Juglandaceae family. Leveraging the recently released whole-genome sequence of C. paliurus, we conducted an in-depth, genome-wide study on the expression of WRKY genes under environmental stresses. We identified 80 CpWRKY genes, classifying them into distinct groups and subgroups based on their structural and phylogenetic characteristics. Synteny analysis and phylogenetic comparison provided insights into the evolutionary traits of these genes. We further investigated the response of the WRKY gene family to salinity stress in combination with the following specific stressors: Methyl jasmonate (MeJA), sodium hydrosulfide (NaHS), and sodium nitroprusside (SNP), which induce the production of signaling molecules jasmonates (JA), hydrogen sulfide (H2S), and nitric oxide (NO), respectively. Our comprehensive analysis of CpWRKY gene expression patterns under various conditions revealed that combined treatments were more effective in inducing up-regulation of CpWRKY gene expression than individual treatments.