title: Arabidopsis transcriptional activators CBF1, CBF2, and CBF3 have matching functional activities.
abstract: When Arabidopsis is exposed to low temperature a small gene family encoding transcription factors known as CBF1, CBF2, and CBF3 (also referred to as DREB1b, DREB1c, and DREB1a, respectively) is rapidly induced followed by expression of CBF-targeted genes, the CBF regulon, which act to bring about an increase in freezing tolerance. 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. Here we explored this issue by comparing the effects that overexpression of each CBF gene had on Arabidopsis growth and development, proline and sugar composition, freezing tolerance and gene expression. Taken together, the results support the conclusion that the CBF1, 2 and 3 transcriptional activators have redundant functional activities.
authors.affiliation: MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA.
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Gilmour
authors.forename: Sarah G
authors.initials: SG
authors.lastname: Fowler
authors.forename: Michael F
authors.initials: MF
authors.lastname: Thomashow
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D015152:Blotting, Northern; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D035264:Flowers / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D005615:Freezing; D005632:Fructose / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D005947:Glucose / Q000378:metabolism; D006026:Glycoside Hydrolases / Q000378:metabolism; D018613:Microscopy, Confocal; D010641:Phenotype; D030821:Plants, Genetically Modified; D011392:Proline / Q000378:metabolism; D013395:Sucrose / Q000378:metabolism; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C104387:CBF1 protein, Arabidopsis; C118228:CBF2 protein, Arabidopsis; D004268:DNA-Binding Proteins; C114578:DREB1A protein, Arabidopsis; D015534:Trans-Activators; D014157:Transcription Factors; D005632:Fructose; D013395:Sucrose; D011392:Proline; D006026:Glycoside Hydrolases; C022514:raffinase; D005947:Glucose