Induction of the Arabidopsis PHO1;H10 gene by 12-oxo-phytodienoic acid but not jasmonic acid via a CORONATINE INSENSITIVE1-dependent pathway.
Expression of AtPHO1;H10, a member of the Arabidopsis (Arabidopsis thaliana) PHO1 gene family, is strongly induced following numerous abiotic and biotic stresses, including wounding, dehydration, cold, salt, and pathogen attack. AtPHO1;H10 expression by wounding was localized to the cells in the close vicinity of the wound site. AtPHO1;H10 expression was increased by application of the jasmonic acid (JA) precursor 12-oxo-phytodienoic acid (OPDA), but not by JA or coronatine. Surprisingly, induction of AtPHO1;H10 by OPDA was dependent on the presence of CORONATINE INSENSITIVE1 (COI1). The induction of AtPHO1;H10 expression by wounding and dehydration was dependent on COI1 and was comparable in both the wild type and the OPDA reductase 3-deficient (opr3) mutant. In contrast, induction of AtPHO1;H10 expression by exogenous abscisic acid (ABA) was independent of the presence of either OPDA or COI1, but was strongly decreased in the ABA-insensitive mutant abi1-1. The involvement of the ABA pathway in regulating AtPHO1;H10 was distinct between wounding and dehydration, with induction of AtPHO1;H10 by wounding being comparable to wild type in the ABA-deficient mutant aba1-3 and abi1-1, whereas a strong reduction in AtPHO1;H10 expression occurred in aba1-3 and abi1-1 following dehydration. Together, these results reveal that OPDA can modulate gene expression via COI1 in a manner distinct from JA, and independently from ABA. Furthermore, the implication of the ABA pathway in coregulating AtPHO1;H10 expression is dependent on the abiotic stress applied, being weak under wounding but strong upon dehydration.
Ribot
Cécile
C
Département de Biologie Moléculaire Végétale, Biophore, Université de Lausanne, CH-1015 Lausanne, Switzerland.
Zimmerli
Céline
C
Farmer
Edward E
EE
Reymond
Philippe
P
Poirier
Yves
Y
D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000502:physiology*; D003517:Cyclopentanes / Q000494:pharmacology*; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D017343:Genes, Plant; D054883:Oxylipins / Q000494:pharmacology*; D015398:Signal Transduction
D029681:Arabidopsis Proteins; C112279:COI1 protein, Arabidopsis; D003517:Cyclopentanes; D005231:Fatty Acids, Unsaturated; D054883:Oxylipins; C025999:12-oxophytodienoic acid; C011006:jasmonic acid