A tomato transcription factor, SlDREB3 enhances the tolerance to chilling in transgenic tomato

The dehydration response factor (DREB) transcription factor (TF) family can function in response to multiple cues around environment in plants. Nevertheless, the functions of dehydration response factor (DREB protein) in plant cold tolerance, especially in tomatoes (Solanum lycopersicum), have been rarely studied. In this study, the functions of tomato DREB TF (SlDREB3) in cold resistance were studied using transgenic tomatoes. The level of transcripts revealed that SlDREB3 was triggered by H₂O₂ and 4 °C treatments, indicating that SlDREB3 participates in response to cold stress in plants. SlDREB3-overexpressing plants exhibited high fresh mass, chlorophyll content, Fv/Fm, and O₂-evolving activity; low membrane damage; and reactive oxygen species accumulation under chilling stress. Furthermore, the high expression levels of late embryogenesis-abundant genes SlLEA9 and SlLEA26 were detected in transgenic plants in response to cold stress. These findings revealed that SlDREB3 overexpression improved the tolerance to cold stress in transgenic plants possibly by upregulating SlLEAs expression.