Transcriptional regulation of SlFRIGIDA-like improve antioxidant system in tomato under cold.

Background: Plant experience exposure to short term low temperature during early spring. In response, it activates various mechanisms to cope with the changing environment. This response involves in the regulation of related genes and hormones, increase signaling cross-talks, antioxidants and osmolytes accumulation to protect the plant from damage. Protein and DNA damage, and lipid peroxidation caused due to extended exposure to cold. It disturbs normal physiological and metabolic processes and thus reduce vigor and growth in plants. FRIGIDA-like is a scaffold protein that play a key role in vernalization pathway to induce flowering.

Results: In this study, OE and OE lines of tomato were exposed to low temperature and its potential response to cold was evaluated. We observed that enzymatic activity was improved in the transgenic lines. The activity of enzymes such as, SOD, POD, CAT, APX, DHAR, and MDHAR was enhanced by regulating its related genes such as , and . Minimum MDA and HO contents, and higher proline contents were found in transgenic lines indicating that -OE can enhance cold stress tolerance in tomato. The transcription of cold related genes including and were increased in the transgenic lines. Moreover, through RNA-sequencing, we found that different pathways related to cold stress were upregulated in the transgenic lines, indicating that it can improve tomato response to cold stress.

Conclusion: These results suggested that, overexpression of s influence enzymatic system by regulating its related genes and through transcriptional regulation of different pathways, it increases cold stress response in tomato.