Functions of rice NAC transcriptional factors, ONAC122 and ONAC131, in defense responses against Magnaporthe grisea

• Published in: Plant molecular biology 2013-01, Vol.81 (1-2), p.41-56
• Main Authors: Sun, Lijun, Zhang, Huijuan, Li, Dayong, Huang, Lei, Hong, Yongbo, Ding, Xin Shun, Nelson, Richard S., Zhou, Xueping, Song, Fengming
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Base Sequence; Biochemistry; Biomedical and Life Sciences; Carboxylic acids; Cloning, Molecular; Defense mechanisms; Disease resistance; DNA, Plant - genetics; Fungi; Gene Expression; Gene Silencing; Genes, Plant; Host-Pathogen Interactions - genetics; Host-Pathogen Interactions - immunology; Host-Pathogen Interactions - physiology; Life Sciences; Magnaporthe - pathogenicity; Molecular biology; Molecular Sequence Data; Oryza - genetics; Oryza - immunology; Oryza - metabolism; Oryza - microbiology; Phylogeny; Plant biology; Plant Diseases - genetics; Plant Diseases - immunology; Plant Diseases - microbiology; Plant growth; Plant Pathology; Plant Proteins - antagonists & inhibitors; Plant Proteins - genetics; Plant Proteins - metabolism; Plant Sciences; Proteins; Rice; Sequence Homology, Amino Acid; Signal Transduction; Transcription Factors - antagonists & inhibitors; Transcription Factors - genetics; Transcription Factors - metabolism
• ISSN: 0167-4412; 1573-5028
• DOI: 10.1007/s11103-012-9981-3

NAC ( N AM/ A TAF/ C UC) transcription factors have important functions in regulating plant growth, development, and abiotic and biotic stress responses. Here, we characterized two rice pathogen-responsive NAC transcription factors, ONAC122 and ONAC131. We determined that these proteins localized to the nucleus when expressed ectopically and had transcriptional activation activities. ONAC122 and ONAC131 expression was induced after infection by Magnaporthe grisea , the causal agent of rice blast disease, and the M. grisea -induced expression of both genes was faster and higher in the incompatible interaction compared with the compatible interaction during early stages of infection. ONAC122 and ONAC131 were also induced by treatment with salicylic acid, methyl jasmonate or 1-aminocyclopropane-1-carboxylic acid (a precursor of ethylene). Silencing ONAC122 or ONAC131 expression using a newly modified Brome mosaic virus (BMV)-based silencing vector resulted in an enhanced susceptibility to M. grisea . Furthermore, expression levels of several other defense- and signaling-related genes (i.e. OsLOX , OsPR1a , OsWRKY45 and OsNH1 ) were down-regulated in plants silenced for ONAC122 or ONAC131 expression via the BMV-based silencing system. Our results suggest that both ONAC122 and ONAC131 have important roles in rice disease resistance responses through the regulated expression of other defense- and signaling-related genes.