CBF1 and CBF4 in Solanum tuberosum L. differ in their effect on low-temperature tolerance and development

Abstract

Cold stress, as an adverse environmental condition that plants experience, dramatically affects plant growth and development, crop productivity and quality. Plants growing in temperate regions encode several C-repeat Binding Factor/Dehydration Responsive Element Binding Factors (CBF/DREB) and whether these transcription factors have different functions should be explored. In this study, we targeted two genes in the CBF family, StCBF1 and StCBF4, which are present in Solanum tuberosum L., that lack a cold acclimation ability. Our results showed that both StCBF1 and StCBF4 transgenic Arabidopsis plants enhanced low-temperature tolerance, the activity of antioxidant enzymes was higher than that of wild-type (WT) plants, and the reactive oxygen species (ROS) accumulation in transgenic plants was less than that in WT plants. StCBFs overexpression coincided with an increase in the expression of the cold-regulated genes AtCOR15a, AtCOR47, AtKIN1 and AtRD29A. Low-temperature tolerance was most increased by StCBF4 overexpression (StCBF4-OE) lines, and development was improved by StCBF1 overexpression (StCBF1-OE) lines and delayed by StCBF4-OE lines. Analysis of gene expression showed that these morphological changes may be due to an increase in the expression of AtRGL3 and AtFLC in StCBF4-OE lines and a decrease in StCBF1-OE lines. However, the increased low-temperature tolerance may be related to the increased expression of some cold-regulated genes (COR genes) in StCBF4-OE lines. Our results suggested that both StCBF1 and StCBF4 can enhance the cold tolerance of Arabidopsis, and StCBF4 plays a more pronounced role than StCBF1 in low-temperature resistance.