title: OsWRKY03, a rice transcriptional activator that functions in defense signaling pathway upstream of OsNPR1.
abstract: WRKY family proteins are a class of plant specific transcription factors that involve in many stress response pathways. It has been shown that one Arabidopsis WRKY protein, AtWRKY29/22, is activated by MAP kinase signaling cascade and confers resistance to both bacterial and fungal pathogens. However, little is known about the biological roles of WRKY proteins in rice. In this study, we investigated the expression patterns of rice AtWRKY29/22 homolog, OsWRKY03, under different conditions, and also its possible role involved in plant defense. Our results showed that OsWRKY03 was up-regulated by several defense signaling molecules or different treatments. Further analysis revealed that the expression of OsWRKY03 was light dependent. Transcriptional activation activity of OsWRKY03 was also demonstrated by yeast functional assay. Transient expression of OsWRKY03-GFP fusion protein in onion epidermis cells showed that OsWRKY03 was a nuclear localized protein. OsNPR1 as well as several other pathogenesis-related genes, such as OsPR1b, phenylalanine ammonia-lyase (ZB8) and peroxidase (POX22.3), were induced in OsWRKY03-overexpressing transgenic plants. These results indicated that OsWRKY03 is located upstream of OsNPR1 as a transcriptional activator in salicylic acid (SA)-dependent or jasmonic acid (JA)-dependent defense signaling cascades.
authors.affiliation: The State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Xiao Qiang
authors.initials: XQ
authors.lastname: Liu
authors.forename: Xian Quan
authors.initials: XQ
authors.lastname: Bai
authors.forename: Qian
authors.initials: Q
authors.lastname: Qian
authors.forename: Xiu Jie
authors.initials: XJ
authors.lastname: Wang
authors.forename: Ming Sheng
authors.initials: MS
authors.lastname: Chen
authors.forename: Cheng Cai
authors.initials: CC
authors.lastname: Chu
mesh_terms: D000595:Amino Acid Sequence; D001692:Biological Transport; D002467:Cell Nucleus; D003001:Cloning, Molecular; D003517:Cyclopentanes / Q000494:pharmacology; D005030:Ethylenes / Q000494:pharmacology; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D008969:Molecular Sequence Data; D012275:Oryza / Q000235:genetics* / Q000378:metabolism*; D054883:Oxylipins; D010641:Phenotype; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020156:Salicylic Acid / Q000494:pharmacology; D036226:Seedlings / Q000187:drug effects; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D015533:Transcriptional Activation / Q000235:genetics*
chemical_list: D003517:Cyclopentanes; D005030:Ethylenes; D054883:Oxylipins; D010940:Plant Proteins; D012333:RNA, Messenger; C011006:jasmonic acid; D020156:Salicylic Acid