Molecular Cloning and Functional Analysis of Rice (Oryza sativa L.) OsNDR1 on Defense Signaling Pathway |
Joo Hee Lee, Sun Hyung Kim, Young Ho Jung, Jung A Kim, Mi Ok Lee, Pil Gyu Choi, Woo Bong Choi, Kyung Nam Kim, Nam Soo Jwa |
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Abstract |
A novel rice (Oryza sativa L.) gene, homologous to Arabidopsis pathogenesis-related NDR1 gene, was cloned from cDNA library prepared from 30 min Magnaporthe grisea -treated rice seedling leaves, and named as OsNDR1. OsNDR1 encoded a 220-aminoacid polypeptide and was highly similar to the Arabidopsis AtNDR1 protein. OsNDR1 is a plasma membrane (PM)-localized protein, and presumes through sequence analysis and protein localization experiment. Overexpression of OsNDR1 promotes the expression of PBZ1 that is essential for the activation of defense/stressrelated gene. The OsNDR1 promoter did not respond significantly to treatments with either SA, PBZ, or ETP. Exogenously applied BTH induces the same set of SAR genes as biological induction, providing further evidence for BTH as a signal. Presumably, BTH is bound by a receptor and the binding triggers a signal transduction cascade that has an ultimate effect on transcription factors that regulate SAR gene expression. Thus OsNDR1 may act as a transducer of pathogen signals and/or interact with the pathogen and is indeed another important step in clarifying the component participating in the defense response pathways in rice. |
Key Words:
Benzo(1, 2, 3)-thiadiazole-7-carbothioic acid Smethyl ester (BTH), Magnaporthe grisea, Oryza sativa L., OsNDR1, system acquired resistance |
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