Cold-inducible transcription factor, CaCBF, is associated with a homeodomain leucine zipper protein in hot pepper (Capsicum annuum L.).
C-Repeat/drought responsive element binding factor (CBF1/DREB1b) is a well known transcriptional activator that is induced at low temperature and in turn induces the CBF regulon (CBF-targeted genes). We have cloned and characterized two CBF1-like cDNAs, CaCBF1A and CaCBF1B, from hot pepper. CaCBF1A and CaCBF1B were not produced in response to mechanical wounding or abscisic acid but were induced by low-temperature stress at 4 degrees . When plants were returned to 25 degrees , their transcript levels of the CBF1-like genes decreased markedly within 40 min. Long-term exposure to chilling resulted in continuous expression of these genes. The critical temperature for induction of CaCBF1A was between 10 and 15 degrees . Low temperature led to its transcription in roots, stems, leaves, fruit without seeds, and apical meristems, and a monoclonal antibody against it revealed a significant increase in CaCBF1A protein by 4 h at 4 degrees . Two-hybrid screening led to the isolation of an homeodomain leucine zipper (HD-Zip) protein that interacts with CaCBF1B. Expression of HD-Zip was elevated by low temperature and drought.
Kim
Sihyun
S
School of Biological Sciences, Seoul National University, Seoul 151-747, Korea.
An
Chung Sun
CS
Hong
Young-Nam
YN
Lee
Kwang-Woong
KW
D000040:Abscisic Acid / Q000378:metabolism; D000595:Amino Acid Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D015153:Blotting, Western; D002212:Capsicum / Q000235:genetics*; D003001:Cloning, Molecular; D003080:Cold Temperature; D018076:DNA, Complementary / Q000378:metabolism; D015723:Gene Library; D005982:Glutathione Transferase / Q000378:metabolism; D016350:Leucine Zippers; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D016133:Polymerase Chain Reaction; D011485:Protein Binding; D014176:Protein Biosynthesis; D017434:Protein Structure, Tertiary; D012313:RNA / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013696:Temperature; D013997:Time Factors; D014018:Tissue Distribution; D014157:Transcription Factors / Q000737:chemistry* / Q000235:genetics; D015533:Transcriptional Activation; D020798:Two-Hybrid System Techniques; D001616:beta-Galactosidase / Q000378:metabolism
D018076:DNA, Complementary; D014157:Transcription Factors; D012313:RNA; D000040:Abscisic Acid; D005982:Glutathione Transferase; D001616:beta-Galactosidase