Disease relevance of CBF1

• CBF/DREB1 (C-repeat-binding factor/dehydration responsive element-binding factor 1) genes encode a small family of transcriptional activators that have been described as playing an important role in freezing tolerance and cold acclimation in Arabidopsis [1].
• A transcriptional activator, CBF1, from Arabidopsis thaliana, which has the AP2 domain for DNA binding and regulates the cold acclimation response, was overexpressed in Escherichia coli, purified, and characterized [2].
• In an attempt to improve stress tolerance of tomato (Lycopersicon esculentum) plants, an expression vector containing an Arabidopsis C-repeat/dehydration responsive element binding factor 1 (CBF1) cDNA driven by a cauliflower mosaic virus 35S promoter was transferred into tomato plants [3].
• Accordingly, transgenic plants that constitutively express CBF1 accumulate less bioactive GA and as a consequence exhibit dwarfism and late flowering [4].

High impact information on CBF1

• We conclude that CBF1 is a likely regulator of the cold acclimation response, controlling the level of COR gene expression, which in turn promotes tolerance to freezing [5].
• Increased expression of Arabidopsis CBF1, a transcriptional activator that binds to the CRT/DRE sequence, induced COR gene expression and increased the freezing tolerance of nonacclimated Arabidopsis plants [5].
• C-repeat binding factor/dehydration responsive element binding factor 1 (Ca2+/H+) antiporters is required for the correct transduction of the signal [6].
• In contrast, cold-inducible expression of genes CBF1, CBF2, CBF3, and ATP5CS1, which lack the CRT/DRE motif, was not affected [7].
• Subtractive hybridization was used to isolate the responsive genes to heterologous CBF1 in transgenic tomato plants and the CAT1 (CATALASE1) was characterized [8].

Biological context of CBF1

• DREB1A and CBF1 were shown to be involved in low-temperature-responsive gene expression [9].
• Light enhanced the induction kinetics of CBF1, 2, and 3 encoding the cognate transcription factors, and cor15a, in a consecutive manner compared to the dark condition in the cold, suggesting that the connection point between cold and light signalling mediated by phytochrome is at a higher step than the expression of CBF genes [10].
• Results from the current study suggest that heterologous CBF1 expression in transgenic tomato plants may induce several oxidative-stress responsive genes to protect from chilling stress [3].
• A DNA cassette containing an Arabidopsis C repeat/dehydration-responsive element binding factor 1 (CBF1) cDNA and a nos terminator, driven by a cauliflower mosaic virus 35S promoter, was transformed into the tomato (Lycopersicon esculentum) genome [8].
• The CBF1, 2 and 3 proteins, though highly similar in amino acid sequence, are not identical, raising the question of whether the proteins have the same functions [11].

Associations of CBF1 with chemical compounds

• In Triticum monococcum, a locus carrying a family of Cbf-like genes, orthologs of Arabidopsis Cbf genes, is tightly linked to the frost tolerance locus Fr-A ( m ) 2, representing candidates for the differences in frost tolerance mapped at this locus [12].

Other interactions of CBF1

• The gene encoding C-repeat/dehydration-responsive element binding factor 1 (CBF1/DREB1b) of Arabidopsis was introduced into rice (Oryza sativa L.) under the control of the maize ubiquitin promoter [13].

Analytical, diagnostic and therapeutic context of CBF1

• The difference between the retention time of CBF1 at 4 degrees C and that at 25 degrees C in gel filtration, and the decrease of the sedimentation coefficient, s20,w, caused by the temperature change from 25 to 3 degrees C, strongly suggested that the cold denaturation was accompanied by the extension of the molecule [2].
• The stomata of the transgenic CBF1 tomato plants closed more rapidly than the wild type after water deficit treatment with or without gibberellic acid pretreatment [8].
• Transgenic expression of CBF1 was proved by northern- and western-blot analyses [3].
• When the expression of eight Cbf genes, previously mapped at the Fr-A2 locus was investigated with gene specific primers using real-time RT-PCR, three Cbf sequences (Cbf1A, Cbf1C, Cbf7) showed a significantly higher relative transcription level (more than fourfold change) in lines differing for the Fr-A2 region [12].

References