title: Functional analysis of allene oxide cyclase, MpAOC, in the liverwort Marchantia polymorpha.
abstract: 12-Oxo-phytodienoic acid (OPDA) is an intermediate in jasmonic acid (JA) biosynthesis. OPDA exerts JA-dependent and JA-independent biological effects; therefore, it is considered a signaling molecule in flowering plants. OPDA is induced by bacterial infection and wounding and inhibits growth in the moss Physcomitrella patens. The functions of OPDA and allene oxide cyclase (AOC) in the liverwort Marchantia polymorpha were explored, which represents the most basal lineage of extant land plants. The analysis of OPDA showed that it is present in M. polymorpha and is increased by wounding. OPDA has been suggested to be involved in the response to environmental stresses. Moreover, OPDA showed growth inhibitory activity in M. polymorpha. Nonetheless JA in M. polymorpha was not found in this study. AOC synthesizes OPDA from an unstable allene oxide. A database search of the M. polymorpha genome identified only a putative gene encoding allene oxide cyclase (MpAOC). Recombinant MpAOC showed AOC activity similar to that in flowering plants. MpAOC was localized to chloroplasts, as in flowering plants. Expression of MpAOC was induced by wounding and OPDA treatment, and positive feedback regulation of OPDA was demonstrated in M. polymorpha. Overexpression of MpAOC increased the endogenous OPDA level and suppressed growth in M. polymorpha. These results indicate the role of OPDA as a signaling molecule regulating growth and the response to wounding in the liverwort M. polymorpha.
authors.affiliation: Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Yamamoto
authors.affiliation: Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Ohshika
authors.affiliation: Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Takahashi
authors.affiliation: Graduate School of Science, Kobe University, Kobe 657-8501, Japan.
authors.forename: Kimitsune
authors.initials: K
authors.lastname: Ishizaki
authors.affiliation: Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kohchi
authors.affiliation: Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Matusuura
authors.affiliation: Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan. Electronic address: kosaku@chem.agr.hokudai.ac.jp.
authors.forename: Kosaku
authors.initials: K
authors.lastname: Takahashi
mesh_terms: D019068:Bryopsida / Q000235:genetics; D003517:Cyclopentanes / Q000378:metabolism*; D005231:Fatty Acids, Unsaturated / Q000378:metabolism; D019746:Intramolecular Oxidoreductases / Q000378:metabolism*; D047008:Marchantia / Q000737:chemistry / Q000201:enzymology / Q000235:genetics; D015394:Molecular Structure; D054883:Oxylipins / Q000378:metabolism*
chemical_list: D003517:Cyclopentanes; D005231:Fatty Acids, Unsaturated; D054883:Oxylipins; C025999:12-oxophytodienoic acid; C011006:jasmonic acid; D019746:Intramolecular Oxidoreductases; C021377:hydroperoxide isomerase
keywords: 12-Oxo-phytodienoic acid; Allene oxide cyclase; Marchantia polymorpha; Marchantiaceae; Octadecanoid pathway; Stress response