The transcription factor DgTCP2 improves chrysanthemum cold tolerance by directly targeting DgFSD1

Low temperature can limit plant growth, development, and production applications. TCP transcription factors, which are specific to plants, play important roles in regulating plant responses to cold stress. However, the mechanisms through which TCP modulates plant responses to cold stress remain poorly understood. In this study, a low-temperature-induced DgTCP2 was identified from Chrysanthemum morifolium Ramat. DgTCP2 overexpression improved cold tolerance of chrysanthemum, while CRISPR-CAS9-mediated gene editing increased its sensitivity to cold stress. DgTCP2 is a nuclear-localized protein with transcriptional activation activity. Subsequent transcriptomic analysis showed that DgTCP2 promoted the expression of the superoxide dismutase gene DgFSD1 . Further analysis revealed that DgTCP2 directly targets DgFSD1 to enhance SOD activity, scavenging excess reactive oxygen species, and thus enhancing cold tolerance in chrysanthemum.This study provides valuable insights into the DgTCP2 -mediated cold stress response and lays the groundwork for developing cold-tolerant chrysanthemum varieties.