Pan-Genome-Based Characterization of the PYL Transcription Factor Family in .

Abscisic acid (ABA) is a key phytohormone involved in regulating plant growth and responses to environmental stress. As receptors of ABA, pyrabactin resistance 1 (PYR)/PYR1-like (PYL) proteins play a central role in initiating ABA signal transduction. In this study, a total of 30 genes were identified and classified into three sub-families (PYL I-III) in the pan-genome of 17 species, through phylogenetic analysis. Among these subfamilies, the PYL I subfamily was the largest, comprising 21 members, whereas PYL III was the smallest, with only four members. To elucidate the evolutionary dynamics of these genes, we conducted synteny and / analyses. Results indicated that most genes had undergone purifying selection (/ < 1), while a few were subject to positive selection (/ > 1). Promoter analysis revealed 258 -regulatory elements in the genes of (EUP) and (PRU), including 127 elements responsive to abiotic stress and 33 ABA-related elements. Furthermore, six structural variations (SVs) were detected in genes and significantly influenced gene expression levels ( < 0.05). To further explore the functional roles of genes, we analyzed tissue-specific expression profiles of 17 genes under drought stress conditions. was predominantly expressed in roots, exhibited leaf-specific expression, and showed elevated expression in stems. These findings suggest that the drought response of genes is tissue-specific. Overall, this study highlights the utility of pan-genomics in elucidating gene family evolution and suggests that genes contribute to the regulation of drought stress responses in EUP, offering valuable genetic resources for functional characterization of genes.