title: Tobacco MAP kinase phosphatase (NtMKP1) negatively regulates wound response and induced resistance against necrotrophic pathogens and lepidopteran herbivores.
abstract: Mitogen-activated protein kinase (MAPK) cascades are universal signal transduction pathways in eukaryotic cells. In tobacco, two MAPK, wound-induced protein kinase (WIPK) and salicylic acid (SA)-induced protein kinase (SIPK), are activated by biotic and abiotic stresses. Both WIPK and SIPK positively regulate the biosynthesis of jasmonic acid (JA) or ethylene (ET) while negatively regulating SA accumulation. We showed previously that recombinant tobacco MAPK phosphatase (NtMKP1) protein dephosphorylates and inactivates SIPK in vitro, and overexpression of NtMKP1 repressed wound-induced activation of both SIPK and WIPK. To elucidate the role of NtMKP1 in response to biotic and abiotic stresses, we generated transgenic tobacco plants in which NtMKP1 expression was suppressed. Suppression of NtMKP1 expression resulted in enhanced activation of WIPK and SIPK and production of both JA and ET upon wounding. Wound-induced expression of JA- or ET-inducible genes, basic PR-1 and PI-II, was also significantly enhanced in these plants. Furthermore, NtMKP1-suppressed plants exhibited enhanced resistance against a necrotrophic pathogen, Botrytis cinerea, and lepidopteran herbivores, Mamestra brassicae and Spodoptera litura. These results suggest that NtMKP1 negatively regulates wound response and resistance against both necrotrophic pathogens and herbivorous insects through suppression of JA or ET pathways via inactivation of MAPK.
authors: National Institute of Agrobiological Science, Tsukuba, Ibaraki, Japan.
authors: Kumiko
authors: K
authors: Oka
authors: Yuta
authors: Y
authors: Amano
authors: Shinpei
authors: S
authors: Katou
authors: Shigemi
authors: S
authors: Seo
authors: Kei
authors: K
authors: Kawazu
authors: Atsushi
authors: A
authors: Mochizuki
authors: Kazuyuki
authors: K
authors: Kuchitsu
authors: Ichiro
authors: I
authors: Mitsuhara
mesh_terms: D000818:Animals; D020171:Botrytis / Q000502:physiology*; D003517:Cyclopentanes / Q000032:analysis / Q000378:metabolism; D054638:Dual Specificity Phosphatase 1 / Q000235:genetics / Q000378:metabolism*; D005030:Ethylenes / Q000032:analysis / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D060434:Herbivory; D007814:Larva; D007915:Lepidoptera / Q000502:physiology*; D020935:MAP Kinase Signaling System; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism; D054883:Oxylipins / Q000032:analysis / Q000378:metabolism; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D010937:Plant Growth Regulators / Q000032:analysis / Q000378:metabolism; D057865:Plant Immunity; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics / Q000276:immunology / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D018749:RNA, Plant / Q000235:genetics; D020156:Salicylic Acid / Q000378:metabolism; D013312:Stress, Physiological; D014026:Nicotiana / Q000201:enzymology* / Q000235:genetics / Q000276:immunology / Q000502:physiology
chemical_list: D003517:Cyclopentanes; D005030:Ethylenes; D054883:Oxylipins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D018749:RNA, Plant; C011006:jasmonic acid; C036216:ethylene; D020928:Mitogen-Activated Protein Kinases; D054638:Dual Specificity Phosphatase 1; D020156:Salicylic Acid