Genome-wide analysis of the PYL gene family and identification of PYL genes that respond to cold stress in Triticum monococcum L. Subsp. Aegilopoides.

Abscisic acid (ABA) is a key plant hormone that regulates plant growth and response to stress . Pyrabactin resistance 1-like (PYR/PYL) proteins are ABA receptors involved in the initial steps of ABA signaling. Triticum monococcum L. subsp. aegilopoides is an important germplasm resource for wheat. In this study, we identified 15 PYL genes from T. monococcum L. subsp. aegilopoides and found that they were distributed across five chromosomes. Based on phylogenetic analysis, we classified these genes into three subfamilies. Members of each subfamily have similar gene structures and contain a common motif. Further analysis revealed that the promoters have multiple hormone-related elements. We found 7, 33, and 49 collinear gene pairs in three different ploidy wheat species (T. urartu, T. turgidum and T. aestivum), indicating that PYL genes are relatively conserved during the process of wheat polyploidization. Additionally, interaction networks and miRNA targets were predicted, revealing interactions between PYL proteins and key components of the abscisic acid signaling network. miR9666b-3p may serve as a central factor in PYL involvement in the abscisic acid network. Through RNA-seq analysis and qPCR validation, three genes (TbPYL2, TbPYL5, and TbPYL12) were found to potentially play a role in cold stress. These findings lay the groundwork for further research on PYL genes in T. monococcum L. subsp. aegilopoides.