Expression and Functional Roles of the Pepper Pathogen-Induced bZIP Transcription Factor CabZIP2 in Enhanced Disease Resistance to Bacterial Pathogen Infection.
A pepper bZIP transcription factor gene, CabZIP2, was isolated from pepper leaves infected with a virulent strain of Xanthomonas campestris pv. vesicatoria. Transient expression analysis of the CabZIP2-GFP fusion protein in Nicotiana benthamiana revealed that the CabZIP2 protein is localized in the cytoplasm as well as the nucleus. The acidic domain in the N-terminal region of CabZIP2 that is fused to the GAL4 DNA-binding domain is required to activate the transcription of reporter genes in yeast. Transcription of CabZIP2 is induced in pepper plants inoculated with virulent or avirulent strains of X. campestris pv. vesicatoria. The CabZIP2 gene is also induced by defense-related hormones such as salicylic acid, methyl jasmonate, and ethylene. To elucidate the in vivo function of the CabZIP2 gene in plant defense, virus-induced gene silencing in pepper and overexpression in Arabidopsis were used. CabZIP2-silenced pepper plants were susceptible to infection by the virulent strain of X. campestris pv. vesicatoria, which was accompanied by reduced expression of defense-related genes such as CaBPR1 and CaAMP1. CabZIP2 overexpression in transgenic Arabidopsis plants conferred enhanced resistance to Pseudomonas syringae pv. tomato DC3000. Together, these results suggest that CabZIP2 is involved in bacterial disease resistance.
1 Department of Life Science (BK21 program), Chung-Ang University, Seoul, 156-756, Republic of Korea;
Chae Woo
CW
Lim
1 Department of Life Science (BK21 program), Chung-Ang University, Seoul, 156-756, Republic of Korea;
Woonhee
W
Baek
1 Department of Life Science (BK21 program), Chung-Ang University, Seoul, 156-756, Republic of Korea;
Sohee
S
Lim
2 Department of Integrative Plant Science, Chung-Ang University, Anseong, 456-756, Republic of Korea.
Sang-Wook
SW
Han
1 Department of Life Science (BK21 program), Chung-Ang University, Seoul, 156-756, Republic of Korea;
Sung Chul
SC
Lee
D000085:Acetates / Q000378:metabolism; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000382:microbiology; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics* / Q000378:metabolism; D002212:Capsicum / Q000235:genetics* / Q000382:microbiology*; D003517:Cyclopentanes / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D060467:Disease Resistance; D005030:Ethylenes / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D054884:Host-Pathogen Interactions / Q000235:genetics*; D008969:Molecular Sequence Data; D054883:Oxylipins / Q000378:metabolism; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D044224:Pseudomonas syringae / Q000472:pathogenicity; D017386:Sequence Homology, Amino Acid; D014026:Nicotiana / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics; D016959:Xanthomonas campestris / Q000472:pathogenicity
D000085:Acetates; D050976:Basic-Leucine Zipper Transcription Factors; D003517:Cyclopentanes; D005030:Ethylenes; D054883:Oxylipins; D010940:Plant Proteins; D014157:Transcription Factors; C072239:methyl jasmonate; C036216:ethylene