Characterization and Identification of Drought-Responsive ABA-Aldehyde Oxidase (AAO) Genes in Potato ( L.).

Abscisic acid (ABA) is an important stress hormone that affects plants' tolerance to stress. Changes in the content of abscisic can have an impact on plant responses to abiotic stress. The abscisic acid aldehyde oxidase (AAO) plays a crucial role in the final step in the synthesis of abscisic acid; therefore, understanding the function of the gene family is of great significance for insight into plants' response to abiotic stresses. In this study, () members were exhaustively explored using genome databases, and nine were identified. Chromosomal location analysis indicated that genes mapped to 4 of the 14 potato chromosomes. Further analyses of gene structure and motif composition showed that members of the specific subfamily showed relatively conserved characteristics. Phylogenetic relationship analysis indicated that StAAOs proteins were divided into three major clades. Promoter analysis showed that most promoters contained cis-elements related to abiotic stress response and plant hormones. The results of tissue-specific expression analysis indicated that was predominantly expressed in the roots. Analysis of transcriptome data revealed that genes responded significantly to drought treatments. Moreover, further qRT-PCR analysis results indicated that not only significantly responded to drought stress but also to various phytohormone (ABA, SA, and MeJA) and abiotic stresses (salt and low temperature), albeit with different expression patterns. In summary, our study provides comprehensive insights into the sequence characteristics, structural properties, evolutionary relationships, and expression patterns of the gene family. These findings lay the foundation for a deeper understanding of the gene family and offer a potential genetic resource for breeding drought-resistant potato varieties.