title: BjMYB1, a transcription factor implicated in plant defence through activating BjCHI1 chitinase expression by binding to a W-box-like element.
abstract: We previously identified the W-box-like-4 (Wbl-4) element (GTAGTGACTCAT), one of six Wbl elements in the BjC-P promoter of the unusual chitinase gene BjCHI1 from Brassica juncea, as the core element responsive to fungal infection. Here, we report the isolation and characterization of the cognate transcription factor interacting with the Wbl-4 element. Using Wbl-4 as a target, we performed yeast one-hybrid screening of a B. juncea cDNA library and isolated an R2R3-MYB transcription factor designated as BjMYB1. BjMYB1 was localized in the nucleus of plant cells. EMSA assays confirmed that BjMYB1 binds to the Wbl-4 element. Transiently expressed BjMYB1 up-regulated the activity of the BjC-P promoter through its binding to the Wbl-4 element in tobacco (Nicotiana benthamiana) leaves. In B. juncea, BjMYB1 displayed a similar induced expression pattern as that of BjCHI1 upon infection by the fungus Botrytis cinerea Moreover, heterogeneous overexpression of BjMYB1 significantly elevated the resistance of transgenic Arabidopsis thaliana to the fungus B. cinerea These results suggest that BjMYB1 is potentially involved in host defence against fungal attack through activating the expression of BjCHI1 by binding to the Wbl-4 element in the BjC-P promoter. This finding demonstrates a novel DNA target of plant MYB transcription factors.
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI), Institute of Crop Science, Chinese Academy of Agriculture Sciences (CAAS), Beijing 100081, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Gao
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI), Institute of Crop Science, Chinese Academy of Agriculture Sciences (CAAS), Beijing 100081, China.
authors.forename: Shuangwei
authors.initials: S
authors.lastname: Jia
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI), Institute of Crop Science, Chinese Academy of Agriculture Sciences (CAAS), Beijing 100081, China.
authors.forename: Chunlian
authors.initials: C
authors.lastname: Wang
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI), Institute of Crop Science, Chinese Academy of Agriculture Sciences (CAAS), Beijing 100081, China.
authors.forename: Fujun
authors.initials: F
authors.lastname: Wang
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI), Institute of Crop Science, Chinese Academy of Agriculture Sciences (CAAS), Beijing 100081, China.
authors.forename: Fajun
authors.initials: F
authors.lastname: Wang
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI), Institute of Crop Science, Chinese Academy of Agriculture Sciences (CAAS), Beijing 100081, China zhaokaijun@caas.cn.
authors.forename: Kaijun
authors.initials: K
authors.lastname: Zhao
mesh_terms: D017360:Arabidopsis / Q000382:microbiology / Q000502:physiology; D020171:Botrytis / Q000502:physiology; D002688:Chitinases / Q000378:metabolism*; D060467:Disease Resistance / Q000502:physiology*; D018506:Gene Expression Regulation, Plant / Q000502:physiology; D009149:Mustard Plant / Q000378:metabolism*; D010940:Plant Proteins / Q000502:physiology*; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000502:physiology; D014026:Nicotiana / Q000378:metabolism; D014157:Transcription Factors / Q000502:physiology*
chemical_list: D010940:Plant Proteins; D014157:Transcription Factors; D002688:Chitinases
keywords: BjMYB1; Botrytis cinerea; MYB transcription factor; W-box-like element.; fungus; pathogen defence