Comparative Identification of LsWRKY Transcription Factors and Transcriptional Response to Abiotic and Biotic Stresses in Lagenaria siceraria

Lagenaria siceraria is an essential horticultural and medicinal crop that is used for its edible fruits and ornamental purposes. WRKY transcription factors have been extensively studied in plant responses to environmental stress; however, there is limited information on their specific functions in L. siceraria. In this study, 51 LsWRKY genes were identified in the L. siceraria genome. The 51 LsWRKYs were divided into classes I, II, and III based on evolutionary analysis. Members of each class have similar conserved motifs and exon-intron structures, and promoter analysis helped identify many cis-regulatory elements associated with growth, hormones, and stress responses. GO terms and KEGG analyses indicated the potential roles of LsWRKY in the regulation of bottle gourd development and acclimation to various environmental stressors. Significant differences in LsWRKY expression were observed between different tissues. The results of RNA-seq and qRT-PCR showed that LsWRKYs were expressed in a tissue- and development-specific manner under normal growth conditions. LsWRKY abundance showed a clear pattern of change related to stress when L. siceraria was exposed to unfavorable environmental conditions. This study provides new insights into the role of LsWRKYs in the growth and stress responses of cucurbits.