Plant Molecular Biology 44: 61–71, 2000.
© 2000 Kluwer Academic Publishers. Printed in the Netherlands.
An Arabidopsis gene induced by wounding functionally homologous to
ınthia Losano Costa
, Paulo Arruda
and Celso Eduardo Benedetti
Centro de Biologia Molecular e Engenharia Gen´etica, Universidade Estadual de Campinas, and
Gen´etica e Evolução, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, CP 6109, CEP
13083970, SP, Brazil (
author for correspondence; e-mail: email@example.com)
Received 20 December 1999; accepted in revised form 2 May 2000
Key words: Arabidopsis, OPR3, ﬂavoprotein oxidoreductase, wounding, methyl jasmonate
The regulation of genes in response to wounding is mediated in part by the octadecanoids 12-oxo-phytodienoic
acid (OPDA), jasmonic acid (JA) and its methyl ester methyl jasmonate (MeJA). We identiﬁed, by differen-
tial display, an Arabidopsis gene (OPR3) induced after wounding. OPR3 is homologous to members of the
ﬂavin mononucleotide (FMN) binding proteins, including the old yellow enzyme (OYE) from yeast and 12-
oxophytodienoate-10,11-reductase (OPR) from Arabidopsis. Transcripts of OPR3 rapidly accumulated in leaves
after woundingand MeJA treatment,buttheywere detected in various tissues of unwoundedplants at relativelylow
levels. Expression of the OPR3 gene was signiﬁcantly reduced in wounded leaves of the coi1 mutant, indicating
partial dependence on jasmonate perception for full induction of the gene. The recombinantproteinof OPR3 cross-
reacted with an antiserum raised against the OYE protein, and showed oxidation of β-NADPHwhenOPDAor
-prostaglandinJ2 (PGJ2), an analogue of OPDA, was used as substrate. β-NADPH oxidation was
not observed when MeJA, which lacks the double bond in the ketone ring, was used as substrate. The recombinant
OPR3 protein also showed β-NADPH oxidation activity in the presence of cyclohexenone,but not cyclohexanone,
suggesting that the enzyme has speciﬁcity to cleavage of oleﬁnic bonds in cyclic enones. The results show that the
OPR3 gene product represents a new OPR of Arabidopsis induced after wounding.
Jasmonic acid and compounds of the octadecanoid
pathway are considered a class of defence signals.
They accumulate in wounded plants (Creelman et al.,
1992) and activate certain wound- and pathogen-
responsive genes (Farmer and Ryan, 1992; Menke
et al., 1999). In addition, plant mutants defective in
jasmonate synthesis or perception are more suscep-
tible to fungi and insect attack (Howe et al., 1996;
McConn et al., 1997; Staswick et al., 1998; Vijayan
et al., 1998). The importance of JA in defence against
herbivores in a natural environment has also been es-
tablished. For instance, a MeJA-elicited response was
The nucleotide sequence data reported will appear in the EMBL,
GenBank and DDBJ Nucleotide Sequence Databases under the
accession AF132212 (OPR3).
shown to be costly to the plant, but beneﬁted individu-
als under attack by herbivores in natural populations
by decreasing the rate of attack and increasing the
production of viable seeds (Baldwin, 1998).
Although JA mediates wound and defence re-
sponses, it probably does not act alone in all circum-
stances. It is becoming clear that other signals act in
conjunction with JA to determine speciﬁc changes in
gene expression after wounding or pathogen infection
(Xu et al., 1994; O’Donnell et al., 1996; Penninckx
et al., 1998; Rojo et al., 1998). Furthermore, a JA-
independent signal transduction controlling wound-
and pathogen-induced gene expression has recently
been identiﬁed in Arabidopsis (Titarenko et al., 1997;
Rojo et al., 1998; Thomma et al., 1998).
We have used the differential display to isolate
Arabidopsis genes that are under the control of the