title: Jasmonoyl-l-isoleucine is required for the production of a flavonoid phytoalexin but not diterpenoid phytoalexins in ultraviolet-irradiated rice leaves.
abstract: Rice produces low-molecular-weight antimicrobial compounds known as phytoalexins, in response to not only pathogen attack but also abiotic stresses including ultraviolet (UV) irradiation. Rice phytoalexins are composed of diterpenoids and a flavonoid. Recent studies have indicated that endogenous jasmonyl-l-isoleucine (JA-Ile) is not necessarily required for the production of diterpenoid phytoalexins in blast-infected or CuCl2-treated rice leaves. However, JA-Ile is required for the accumulation of the flavonoid phytoalexin, sakuranetin. Here, we investigated the roles of JA-Ile in UV-induced phytoalexin production. We showed that UV-irradiation induces the biosynthesis of JA-Ile and its precursor jasmonic acid. We also showed that rice jasmonate biosynthesis mutants produced diterpenoid phytoalexins but not sakuranetin in response to UV, indicating that JA-Ile is required for the production of sakuranetin but not diterpenoid phytoalexins in UV-irradiated rice leaves.
authors.affiliation: a Department of Biosciences , Teikyo University , Utsunomiya , Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Miyamoto
authors.affiliation: a Department of Biosciences , Teikyo University , Utsunomiya , Japan.
authors.forename: Isami
authors.initials: I
authors.lastname: Enda
authors.affiliation: a Department of Biosciences , Teikyo University , Utsunomiya , Japan.
authors.forename: Toshiki
authors.initials: T
authors.lastname: Okada
authors.affiliation: a Department of Biosciences , Teikyo University , Utsunomiya , Japan.
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Sato
authors.affiliation: a Department of Biosciences , Teikyo University , Utsunomiya , Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Watanabe
authors.affiliation: a Department of Biosciences , Teikyo University , Utsunomiya , Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Sakazawa
authors.affiliation: a Department of Biosciences , Teikyo University , Utsunomiya , Japan.
authors.forename: Emi
authors.initials: E
authors.lastname: Yumoto
authors.affiliation: a Department of Biosciences , Teikyo University , Utsunomiya , Japan.
authors.forename: Kyomi
authors.initials: K
authors.lastname: Shibata
authors.affiliation: a Department of Biosciences , Teikyo University , Utsunomiya , Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Asahina
authors.affiliation: b Botanical Gardens , Osaka City University , Katano , Japan.
authors.forename: Moritoshi
authors.initials: M
authors.lastname: Iino
authors.affiliation: a Department of Biosciences , Teikyo University , Utsunomiya , Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Yokota
authors.affiliation: c Biotechnology Research Center , The University of Tokyo , Bunkyo-ku , Japan.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Okada
authors.affiliation: a Department of Biosciences , Teikyo University , Utsunomiya , Japan.
authors.forename: Hisakazu
authors.initials: H
authors.lastname: Yamane
mesh_terms: D003517:Cyclopentanes / Q000378:metabolism*; D004224:Diterpenes / Q000737:chemistry; D005419:Flavonoids / Q000737:chemistry*; D007532:Isoleucine / Q000031:analogs & derivatives* / Q000378:metabolism; D012275:Oryza / Q000378:metabolism* / Q000502:physiology / Q000528:radiation effects*; D018515:Plant Leaves / Q000378:metabolism* / Q000502:physiology / Q000528:radiation effects; D012717:Sesquiterpenes / Q000737:chemistry / Q000378:metabolism*; D014466:Ultraviolet Rays / Q000009:adverse effects*; D000094162:Phytoalexins
chemical_list: D003517:Cyclopentanes; D004224:Diterpenes; D005419:Flavonoids; D012717:Sesquiterpenes; C532883:jasmonoyl-isoleucine; D007532:Isoleucine; D000094162:Phytoalexins
keywords: defense response; jasmonic acid; phytoalexin; rice; ultraviolet irradiation