Tomato (Solanum lycopersicum) is an economically important vegetable worldwide, but low temperature severely restricts its growth and yield. Although the transcription factor 3 (BTF3) relates to stress tolerance in many plants, its function in tomato cold resistance remains unclear. Here, we generated SlBTF3-overexpression (SlBTF3-OE) lines and generated slbtf3 knockout mutants. Compared with wild type, SlBTF3-OE plants showed enhanced cold tolerance, while mutants were more sensitive to cold. SlBTF3 interacts and stabilizes the key cold-response protein SlCBF1 and is phosphorylated by SlOST1. It maintains chloroplast integrity, promotes antioxidant enzyme activity, and upregulates photosynthesis-related genes under cold conditions. In summary, this study reveals the mechanism of SlBTF3-mediated cold tolerance and provides a foundation for cold-resistant tomato breeding.
Ning et al. (Fri,) studied this question.