A rice isoflavone reductase-like gene, OsIRL, is induced by rice blast fungal elicitor.
We have isolated and characterized a rice isoflavone reductase-like gene, OsIRL, whose expression is induced by a fungal elicitor. The OsIRL cDNA contains 1203 bp with an open reading frame of 942 nucleotides encoding 314 amino acids. The deduced amino acid sequence of OsIRL has a putative pyridine nucleotide binding domain and is 68% homologous with the maize isoflavone reductase-like gene. Southern blot analysis revealed that OsIRL belongs to a small multigene family. Expression of OsIRL was induced by treatment with a fungal elicitor and jasmonic acid as well as by inoculation with rice blast fungus. Cycloheximide (1 microM), strongly inhibited the induction of OsIRL by the fungal elicitor, indicating that new protein synthesis is required. The protein kinase inhibitor, staurosporine (1 microM), had little effect, but the phosphatase inhibitor, calyculin A (1 microM), strongly inhibited induction. Treatment with salicylic acid (SA, 5 mM) strongly inhibited expression of OsIRL in response to fungal elicitor and JA, while abscisic acid (ABA, 200 microM) also strongly antagonized OsIRL induction by JA, but had only a weak effect on induction by the fungal elicitor. These results suggest that the expression of OsIRL is positively regulated by phytohormones such as JA, and negatively by phytohormones such as SA, ABA.
Kim
Sun Tae
ST
Division of Applied Life Science (Brain Korea 21 Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701, Korea.
Cho
Kyu Seong
KS
Kim
Sang Gon
SG
Kang
Sun Young
SY
Kang
Kyu Young
KY
D000040:Abscisic Acid / Q000494:pharmacology; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D003513:Cycloheximide / Q000494:pharmacology; D003517:Cyclopentanes / Q000494:pharmacology; D018076:DNA, Complementary / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000235:genetics*; D017343:Genes, Plant / Q000235:genetics*; D020461:Madurella / Q000378:metabolism*; D008969:Molecular Sequence Data; D012275:Oryza / Q000235:genetics*; D054883:Oxylipins; D010937:Plant Growth Regulators / Q000494:pharmacology; D017386:Sequence Homology, Amino Acid; D019311:Staurosporine / Q000494:pharmacology; D003313:Zea mays / Q000235:genetics
D003517:Cyclopentanes; D018076:DNA, Complementary; D054883:Oxylipins; D010937:Plant Growth Regulators; C011006:jasmonic acid; D000040:Abscisic Acid; D003513:Cycloheximide; D019311:Staurosporine