Open AccessElucidation of XA21‐mediated innate immunity
Author(s) -
Park ChangJin,
Han SangWook,
Chen Xuewei,
Ronald Pamela C.
Publication year - 2010
Publication title -
cellular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.542
H-Index - 138
eISSN - 1462-5822
pISSN - 1462-5814
DOI - 10.1111/j.1462-5822.2010.01489.x
Subject(s) - biology , xanthomonas oryzae , innate immune system , xanthomonas , gene , xanthomonas oryzae pv. oryzae , genetics , wrky protein domain , arabidopsis , plant disease resistance , plant immunity , microbiology and biotechnology , receptor , mutant
Summary In the early 1970s, the Xa21 gene from the wild rice species Oryza longistaminata drew attention of rice breeders because of its broad‐spectrum resistance to diverse strains of a serious bacterial disease of rice in Asia and Africa, called ‘bacterial blight disease’, caused by the Gram‐negative bacterium, Xanthomonas oryzae pv. oryzae ( Xoo ). In 1995, we isolated the gene controlling this resistance and in 2009 demonstrated that XA21 recognizes a highly conserved peptide, called ‘Ax21’ (activator of XA21‐mediated immunity). Tyrosine sulfation of Ax21 is required for recognition by rice XA21. A decade of genetic, molecular and biochemical studies have uncovered key components of the XA21‐mediated signalling cascade. Ax21 recognition by XA21 at the cell surface induces phosphorylation‐mediated events, which are predicted to alter subcellular localization and/or DNA‐binding activity of a WRKY family of transcription factors. Because XA21 is representative of the large number of predicted pattern recognition receptors (PRRs) in rice ( n = 328), Arabidopsis ( n = 35) and other plant species, further characterization of XA21‐mediated signalling pathways will contribute to elucidation of these important defence responses.