Rice WRKY11 Plays a Role in Pathogen Defense and Drought Tolerance

• Main Authors: Heyoung Lee, Jooyoung Cha, Changhyun Choi, Naeyoung Choi, Hyun-So Ji, Sang Ryeol Park, Seungbum Lee, Duk-Ju Hwang
• Format: Article
• Language: English
• Published: SpringerOpen 2018-01-01
• Series: Rice
• Subjects: OsWRKY11; Disease resistance; Drought tolerance; Cross-talk; Rice
• Online Access: http://link.springer.com/article/10.1186/s12284-018-0199-0
• ISSN: 1939-8425; 1939-8433

Abstract Background Plants are frequently subjected to abiotic and biotic stresses, and WRKY proteins play a pivotal role in the response to such stress. OsWRKY11 is induced by pathogens, drought, and heat, suggesting a function in biotic and abiotic stress responses. Results This study identified OsWRKY11, a member of WRKY group IIc. It is a transcriptional activator that localized to the nucleus. Ectopic expression of OsWRKY11 resulted in enhanced resistance to a bacterial pathogen, Xanthomonas oryzae pv. oryzae; resistance was compromised in transgenic lines under-expressing OsWRKY11. Ectopic expression of OsWRKY11 resulted in constitutive expression of defense-associated genes, whereas knock-down (kd) of OsWRKY11 reduced expression of defense-associated genes during pathogen attack, suggesting that OsWRKY11 activates defense responses. OsWRKY11 bound directly to the promoter of CHITINASE 2, a gene associated with defense, and activated its transcription. In addition, ectopic expression of OsWRKY11 enhanced tolerance to drought stress and induced constitutive expression of drought-responsive genes. Induction of drought-responsive genes was compromised in OsWRKY11-kd plants. OsWRKY11 also bound directly to the promoter of a drought-responsive gene, RAB21, activating its transcription. In addition, OsWRKY11 protein levels were controlled by the ubiquitin-proteasome system. Conclusion OsWRKY11 integrates plant responses to pathogens and abiotic stresses by positively modulating the expression of biotic and abiotic stress-related genes.