Overexpression of MbICE3 increased the tolerance to cold and drought in lettuce (Lactuca sativa L.).

Apple growth and development can be impacted by abiotic factors, including low temperature and dryness. Plant responses to stressors are heavily influenced by inducer of CBF expression (ICE) transcription factors (TFs). Malus baccata (L.) Borkh (M. baccata) was used in this investigation to isolate the MbICE3 new ICE gene. The molecular weight of MbICE3 was anticipated to be 56.47 kDa, and its open reading frame (ORF) had 519 amino acids (aa) and 1560 base pairs (bp). Subcellular localization revealed that MbICE3 was concentrated in the nucleus. Cold and drought stresses significantly affected the expression levels of MbICE3, and the first heterologous expression of MbICE3 in lettuce (Lactuca sativa L.) could significantly improve its tolerance to cold and drought stresses. In comparison to wild-type (WT) and unloaded lines (UL) lettuce, the transgenic plants had increased proline and chlorophyll concentrations as well as higher superoxide dismutase (SOD) and peroxidase (POD) activity when subjected to cold and drought. However, compared to WT and UL, transgenic lettuce had lower levels of malondialdehyde (MDA) and O2− content. Furthermore, it was found that under drought and low temperature stress, MbICE3 positively regulated the expression of LsCBFs genes. These results suggest that MbICE3 actively contributes to plant tolerance to cold and drought. [ABSTRACT FROM AUTHOR]