OsWRKY53

Function:

  OsWRKY53 is a transcription factor that plays important roles in chitin oligosaccharide elicitor-induced defense signaling pathways in rice.OsWRKY53 was also induced in suspension-cultured rice cells by a fungal cerebroside elicitor and in rice plants by infection with the blast fungus Magnaporthe grisea. OsWRKY53 is a transcriptional activator and specifically bound to W-box elements,overexpression of OsWRKY53 in rice plants resulted in enhanced resistance to M. grisea.
 
  WRKY proteins form a large family of plant-specific transcription factors that specifically bind to the W-box elements  (T)TGAC(C/T) and appear to play a regulatory role in a variety of stress responses.WRKY proteins have been investigated extensively for their possible involvement in defense responses against attacks by pathogens, mainly in dicotyledonous plants such as Arabidopsis and tobacco . The rice genome is predicted to contain over 100 Oryza sativa L.WRKY (OsWRKY)genes. 
  3.1. cDNA cloning and expression analysis of OsWRKY53
  A full-length cDNA of OsWRKY53 (AK121190; named by Xie et al.) was isolated from elicited suspension-cultured rice cells by RT-PCR using primers that were designed based on information from a rice genome database. The nucleotide sequence of the OsWRKY53 cDNA reported in this paper will appear in the DNA Data Bank of Japan (DDBJ) nucleotide sequence database under the accession number AB190436.
  All known WRKY proteins contain up to two WRKY domains and are classified based on both the number of WRKY domains and the features of their zinc finger-like motifs. OsWRKY53 belongs to group I, which is characterized by two WRKY domains that contain the Cys2His2 zinc finger-like motif. To investigate the involvement of OsWRKY53 in defense responses to pathogen infection, we examined its expression using Northern hybridization. The elicitor-induced changes in the steady-state levels of the OsWRKY53 mRNA in suspensioncultured rice cells are shown in Fig. 1a. The mRNA level peaked

0.5 h after the addition of each elicitor (chitin oligosaccharide and fungal cerebroside elicitors), and decreased gradually thereafter. We also analyzed the expression pattern of OsWRKY53 in rice plants (cv. Nipponbare) inoculated with the fungal pathogen M. grisea race 007, which is compatible with cv. Nipponbare.