Genome-Wide Identification of the CRY Gene Family in Solanum tuberosum and Response to Abiotic Stresses

Background: Cryptochromes (CRYs) are not only blue-light receptors in plants but also participate in abiotic stress responses, making them essential for plant growth and development. Methods: In this study, the CRY gene family in potato (StCRY) was identified and analyzed using bioinformatics approaches, and the expression patterns of StCRY genes under different abiotic stresses were validated through transcriptome datasets and RT-qPCR analysis. Results: A total of 7 StCRY genes were identified, unevenly distributed across 4 chromosomes. The StCRY genes exhibit conserved structures, with predicted subcellular localization primarily in the nucleus, cytoplasm, and plastids. Promoter region analysis revealed the significant presence of cis-acting elements related to light, plant growth and development, hormones, and stress responses. Phylogenetic analysis classified the CRY gene family into three subgroups and identified one pair of collinear genes. StCRY genes show a closer evolutionary relationship with tomato, followed by Arabidopsis thaliana, and are least related to rice. Transcriptome and RT-qPCR analyses under cold, drought, and salt stresses revealed differential expression among StCRY genes: StCRY3 and StCRY7 respond positively to cold stress, StCRY1 and StCRY5 are upregulated under drought and salt stresses, and StCRY7 expression is positively correlated with salt stress. Conclusions: Collectively, this study provides a preliminary characterization of the CRY gene family in potato and establishes a theoretical foundation for further investigations into the molecular mechanisms of blue-light receptors in abiotic stress responses.