title: Phytochrome A requires jasmonate for photodestruction.
abstract: The plant photoreceptor phytochrome is organised in a small gene family with phytochrome A (phyA) being unique, because it is specifically degraded upon activation by light. This so called photodestruction is thought to be important for dynamic aspects of sensing such as measuring day length or shading by competitors. Signal-triggered proteolytic degradation has emerged as central element of signal crosstalk in plants during recent years, but many of the molecular players are still unknown. We therefore analyzed a jasmonate (JA)-deficient rice mutant, hebiba, that in several aspects resembles a mutant affected in photomorphogenesis. In this mutant, the photodestruction of phyA is delayed as shown by in vivo spectroscopy and Western blot analysis. Application of methyl-JA (MeJA) can rescue the delayed phyA photodestruction in the mutant in a time- and dose-dependent manner. Light regulation of phyA transcripts thought to be under control of stable phytochrome B (phyB) is still functional. The delayed photodestruction is accompanied by an elevated sensitivity of phytochrome-dependent growth responses to red and far-red light.
authors.affiliation: Institute of Botany 1, Universität Karlsruhe, Kaiserstrasse 2, 76128 Karlsruhe, Germany. michael.riemann@bio.uka.de
authors.forename: Michael
authors.initials: M
authors.lastname: Riemann
authors.forename: Daniel
authors.initials: D
authors.lastname: Bouyer
authors.forename: Akiko
authors.initials: A
authors.lastname: Hisada
authors.forename: Axel
authors.initials: A
authors.lastname: Müller
authors.forename: Osamu
authors.initials: O
authors.lastname: Yatou
authors.forename: Elmar W
authors.initials: EW
authors.lastname: Weiler
authors.forename: Makoto
authors.initials: M
authors.lastname: Takano
authors.forename: Masaki
authors.initials: M
authors.lastname: Furuya
authors.forename: Peter
authors.initials: P
authors.lastname: Nick
mesh_terms: D000085:Acetates / Q000494:pharmacology; D015153:Blotting, Western; D018548:Cotyledon / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects; D003517:Cyclopentanes / Q000378:metabolism* / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000528:radiation effects; D007210:Indoleacetic Acids / Q000378:metabolism; D008027:Light; D009154:Mutation / Q000235:genetics; D012275:Oryza / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects*; D054883:Oxylipins / Q000378:metabolism* / Q000494:pharmacology; D051942:Phytochrome A / Q000235:genetics / Q000378:metabolism*; D011499:Protein Processing, Post-Translational / Q000187:drug effects / Q000528:radiation effects*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D013997:Time Factors
chemical_list: D000085:Acetates; D003517:Cyclopentanes; D007210:Indoleacetic Acids; D054883:Oxylipins; D051942:Phytochrome A; D012333:RNA, Messenger; C011006:jasmonic acid; C072239:methyl jasmonate