ICE1: a regulator of cold-induced transcriptome and freezing tolerance in Arabidopsis.
Cold temperatures trigger the expression of the CBF family of transcription factors, which in turn activate many downstream genes that confer chilling and freezing tolerance to plants. We report here the identification of ICE1 (inducer of CBF expression 1), an upstream transcription factor that regulates the transcription of CBF genes in the cold. An Arabidopsis ice1 mutant was isolated in a screen for mutations that impair cold-induced transcription of a CBF3 promoter-luciferase reporter gene. The ice1 mutation blocks the expression of CBF3 and decreases the expression of many genes downstream of CBFs, which leads to a significant reduction in plant chilling and freezing tolerance. ICE1 encodes a MYC-like bHLH transcriptional activator. ICE1 binds specifically to the MYC recognition sequences in the CBF3 promoter. ICE1 is expressed constitutively, and its overexpression in wild-type plants enhances the expression of the CBF regulon in the cold and improves freezing tolerance of the transgenic plants.
Chinnusamy
Viswanathan
V
Department of Plant Sciences, University of Arizona, Tucson 85721, USA.
Ohta
Masaru
M
Kanrar
Siddhartha
S
Lee
Byeong-Ha
BH
Hong
Xuhui
X
Agarwal
Manu
M
Zhu
Jian-Kang
JK
D000064:Acclimatization / Q000502:physiology*; D017360:Arabidopsis / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000502:physiology*; D051792:Basic Helix-Loop-Helix Proteins; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D005615:Freezing; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D016259:Genes, myc / Q000235:genetics; D049452:Green Fluorescent Proteins; D018257:Helix-Loop-Helix Motifs / Q000235:genetics; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008164:Luminescent Proteins / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics; D015534:Trans-Activators / Q000235:genetics / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D014158:Transcription, Genetic / Q000235:genetics*
D029681:Arabidopsis Proteins; D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D049452:Green Fluorescent Proteins; D008156:Luciferases; D008164:Luminescent Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C104387:CBF1 protein, Arabidopsis; C118228:CBF2 protein, Arabidopsis; C114578:DREB1A protein, Arabidopsis