Overexpression of galactinol synthase 1 from Solanum commersonii (ScGolS1) confers freezing tolerance in transgenic potato

Potato (Solanum tuberosum L.) is the fourth largest food crop in world. Low temperatures cause serious damage to potato plants every year, and freezing tolerance has become a hot spot research. Galactinol synthase (GolS) key enzyme synthesis of raffinose family oligosaccharides (RFOs), plays an important role response abiotic stress. In this study, ScGolS1 gene from Solanum commersonii was cloned introduced into S. cultivars ‘Atlantic’ ‘Desiree’ via Agrobacterium-mediated transformation. Phenotyping assays showed that overexpression could significantly improve transgenic plants. Further physiological biochemical experiments lines had lower relative conductivity, malondialdehyde content, 3,3′-diaminobenzidine staining higher plant survival rate compared with wild type (WT) under cold Moreover, C-repeat binding factors (CBF1, CBF2 CBF3), downstream cold-responsive genes COR413 COR47, ethylene-responsive factor (ERF) transcription ERF3, ERF4 ERF6, which function ethylene signaling pathway, were all induced by treatment expressed at levels WT. Besides, expression some such as MIPS, STS RS RFO metabolic pathway up-regulated stress, resulting changes content soluble sugars. This indicated altered sugar composition enhanced inducing CBF pathways. These results provided theoretical support genetic resources for breeding potato.