Overexpression of C-Repeat Binding Factor1 (CBF1) Gene Enhances Heat Stress Tolerance in Arabidopsis

High temperature affects plant growth, development, and seed production. We generated Arabidopsis transgenic plants overexpressing abiotic stress-tolerance associated genes (CBF1, GolS1, NDPK2, YUC6, and PRE1) to investigate the effects of these genes on heat stress (HS) tolerance. We evaluated thermotolerance by assessing the survival rate of T₂ seedlings under acute HS conditions. C-repeat binding factor 1-overexpressing (CBF1-OE) plants exhibited drastically improved HS tolerance, whereas overexpression of the other examined genes yielded marginal effects. Consistent with the ability of CBF1 to regulate transcription, we found that the transcription of several heat-shock inducible genes was remarkably increased in CBF1-OE plants under HS conditions. Furthermore, the expression of several reactive oxygen species (ROS)-responsive genes related to oxidative stress was notably upregulated in CBF1-OE plants. Thus, the thermotolerance of CBF1-OE plants is at least partly associated with the elevated expression of several HS-inducible and ROS-responsive genes. Our study showed that CBF1 plays a role in increasing HS tolerance in Arabidopsis in addition to its previously established roles in cold/drought tolerance.