Nitric oxide function and signalling in plant disease resistance

• Published in: Journal of experimental botany 2008-02, Vol.59 (2), p.147-154
• Main Authors: Hong, Jeum Kyu, Yun, Byung-Wook, Kang, Jeong-Gu, Raja, Muhammad Usman, Kwon, Eunjung, Sorhagen, Kirsti, Chu, Chengcai, Wang, Yiqin, Loake, Gary J
• Format: Article
• Language: English
• Subjects: Biochemistry; Biological and medical sciences; Cell death; Cell Death - physiology; Cell physiology; Disease resistance; Enzymes; Focus Papers: Redox Signalling and Plant Stress; Fundamental and applied biological sciences. Psychology; Gene expression regulation; Hypersensitive response; Molecular and cellular biology; nitric oxide; Nitric Oxide - biosynthesis; Nitric Oxide - chemistry; Nitric Oxide - physiology; Oxides; Pathogens; Plant cells; plant disease resistance; Plant diseases; Plant Diseases - immunology; Plant Proteins - metabolism; Plants; Plants - immunology; Plants - metabolism; Protein Processing, Post-Translational; S-nitrosothiols; S-nitrosylation; Signal transduction; Signal Transduction - physiology
• ISSN: 0022-0957; 1460-2431
• DOI: 10.1093/jxb/erm244

Nitric oxide (NO) is one of only a handful of gaseous signalling molecules. Its discovery as the endothelium-derived relaxing factor (EDRF) by Ignarro revolutionized how NO and cognate reactive nitrogen intermediates, which were previously considered to be toxic molecules, are viewed. NO is now emerging as a key signalling molecule in plants, where it orchestrates a plethora of cellular activities associated with growth, development, and environmental interactions. Prominent among these is its function in plant hypersensitive cell death and disease resistance. While a number of sources for NO biosynthesis have been proposed, robust and biologically relevant routes for NO production largely remain to be defined. To elaborate cell death during an incompatible plant-pathogen interaction NO functions in combination with reactive oxygen intermediates. Furthermore, NO has been shown to regulate the activity of metacaspases, evolutionary conserved proteases that may be intimately associated with pathogen-triggered cell death. NO is also thought to function in multiple modes of plant disease resistance by regulating, through S-nitrosylation, multiple nodes of the salicylic acid (SA) signalling pathway. These findings underscore the key role of NO in plant-pathogen interactions.