Jasmonates induce both defense responses and communication in monocotyledonous and dicotyledonous plants.
Jasmonic acid (JA) and its derivatives (jasmonates, JAs) are phytohormones with essential roles in plant defense against pathogenesis and herbivorous arthropods. Both the up- and down-regulation of defense responses are dependent on signaling pathways mediated by JAs as well as other stress hormones (e.g. salicylic acid), generally those involving the transcriptional and post-transcriptional regulation of transcription factors via protein modification and epigenetic regulation. In addition to the typical model plant Arabidopsis (a dicotyledon), advances in genetics research have made rice a model monocot in which innovative pest control traits can be introduced and whose JA signaling pathway can be studied. In this review, we introduce the dynamic functions of JAs in plant defense strategy using defensive substances (e.g. indole alkaloids and terpenoid phytoalexins) and airborne signals (e.g. green leaf volatiles and volatile terpenes) in response to biotrophic and necrotrophic pathogens as well as above-ground and below-ground herbivores. We then discuss the important issue of how the mutualism of herbivorous arthropods with viruses or bacteria can cause cross-talk between JA and other phytohormones to counter the defense systems.
Biotechnology Research Center, The University of Tokyo, Tokyo, 113-8657 Japan.
Kazunori
K
Okada
Experimental Plant Division, RIKEN BioResource Center, Tsukuba, 305-0074 Japan.
Hiroshi
H
Abe
Department of Biological Science & Technology, Faculty of Industrial Science & Technology, Tokyo University of Science, Tokyo, 125-8585 Japan garimura@rs.tus.ac.jp.
Gen-ichiro
G
Arimura
D003517:Cyclopentanes / Q000378:metabolism*; D044127:Epigenesis, Genetic; D018506:Gene Expression Regulation, Plant; D054884:Host-Pathogen Interactions; D054883:Oxylipins / Q000378:metabolism*; D010935:Plant Diseases / Q000276:immunology*; D010937:Plant Growth Regulators / Q000378:metabolism*; D018515:Plant Leaves / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D010944:Plants / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D020156:Salicylic Acid / Q000378:metabolism; D012717:Sesquiterpenes / Q000737:chemistry / Q000378:metabolism; D015398:Signal Transduction; D013312:Stress, Physiological; D013559:Symbiosis; D055549:Volatile Organic Compounds / Q000737:chemistry / Q000378:metabolism; D000094162:Phytoalexins
D003517:Cyclopentanes; D054883:Oxylipins; D010937:Plant Growth Regulators; D012717:Sesquiterpenes; D055549:Volatile Organic Compounds; C011006:jasmonic acid; D020156:Salicylic Acid; D000094162:Phytoalexins
Jasmonates; Plant defense response; Specialized metabolites; Transcription factor; Volatile organic compounds