Systematic Analysis of Galactinol Synthase and Raffinose Synthase Gene Families in Potato and Their Expression Patterns in Development and Abiotic Stress Responses

Raffinose family oligosaccharides (RFOs) are very important for plant growth, development, and abiotic stress tolerance. Galactinol synthase (GolS) and raffinose synthase (RFS) are critical enzymes involved in RFO biosynthesis. However, the whole-genome identification and stress responses of their coding genes in potato remain unexplored. In this study, four StGolS and nine StRFS genes were identified and classified into three and five subgroups, respectively. Remarkably, a total of two StGolS and four StRFS genes in potato were identified to form collinear pairs with those in both Arabidopsis and tomato, respectively. Subsequent analysis revealed that StGolS4 exhibited significantly high expression levels in transport-related tissues, PEG-6000, and ABA treatments, with remarkable upregulation under salt stress. Additionally, StRFS5 showed similar responses to StGolS4, but StRFS4 and StRFS8 gene expression increased significantly under salt treatment and decreased in PEG-6000 and ABA treatments. Overall, these results lay a foundation for further research on the functional characteristics and molecular mechanisms of these two gene families in response to ABA, salt, and drought stresses, and provide a theoretical foundation and new gene resources for the abiotic-stress-tolerant breeding of potato.

Automated summary

This study identified four StGolS and nine StRFS genes in potato and classified them into three and five subgroups, respectively. Two StGolS and four StRFS genes were found to form collinear pairs with those in Arabidopsis and tomato. Further analysis revealed that StGolS4 showed high expression levels in transport-related tissues, PEG-6000, and ABA treatments, with significant upregulation under salt stress. Additionally, StRFS5 showed similar responses to StGolS4, while StRFS4 and StRFS8 gene expression significantly increased under salt treatment and decreased in PEG-6000 and ABA treatments. These findings lay a foundation for studying the functional characteristics and molecular mechanisms of these gene families in response to ABA, salt, and drought stresses, and provide new gene resources for breeding abiotic-stress-tolerant potatoes.