novel blast resistance gene, Pi54rh cloned from wild species of rice, Oryza rhizomatis confers broad spectrum resistance to Magnaporthe oryzae

• Published in: Functional & integrative genomics 2012-06, Vol.12 (2), p.215-228
• Main Authors: Das, Alok, Soubam, D, Singh, P. K, Thakur, S, Singh, N. K, Sharma, T. R
• Format: Article
• Language: English
• Subjects: 3' Untranslated regions; Animal Genetics and Genomics; Biochemistry; Bioinformatics; Biological and medical sciences; Biomedical and Life Sciences; blast disease; breeding; Cell Biology; Cloning; Cloning, Molecular; Complementation; Disease resistance; Disease Resistance - genetics; Fundamental and applied biological sciences. Psychology; Gene Expression; Gene Expression Regulation, Plant; General aspects; genes; Genes, Plant; Genetic Complementation Test; Genomics; Geographical distribution; Glycosylation; Leaves; Life Sciences; Magnaporthe - physiology; Magnaporthe oryzae; Mathematics in biology. Statistical analysis. Models. Metrology. Data processing in biology (general aspects); Microbial Genetics and Genomics; Mining; Molecular Sequence Annotation; myristoylation; Original Paper; Oryza; Oryza - genetics; Oryza - immunology; Oryza - microbiology; Oryza sativa; Pathogens; Phosphorylation; Phylogeny; Plant breeding; Plant diseases; Plant Diseases - microbiology; Plant Genetics and Genomics; Plant Proteins - genetics; Plant Proteins - metabolism; Plant resistance; Plants, Genetically Modified - genetics; Plants, Genetically Modified - immunology; Plants, Genetically Modified - microbiology; Promoters; Protein Structure, Secondary; Protein Structure, Tertiary; proteins; Rice; rice blast; Selective breeding; Sequence Analysis, DNA; Signal transduction; Transcription; zinc finger motif; Zinc finger proteins
• ISSN: 1438-793X; 1438-7948
• DOI: 10.1007/s10142-012-0284-1

The dominant rice blast resistance gene, Pi54 confers resistance to Magnaporthe oryzae in different parts of India. In our effort to identify more effective forms of this gene, we isolated an orthologue of Pi54 named as Pi54rh from the blast-resistant wild species of rice, Oryza rhizomatis, using allele mining approach and validated by complementation. The Pi54rh belongs to CC-NBS-LRR family of disease resistance genes with a unique Zinc finger (C3H type) domain. The 1,447 bp Pi54rh transcript comprises of 101 bp 5′-UTR, 1,083 bp coding region and 263 bp 3′-UTR, driven by pathogen inducible promoter. We showed the extracellular localization of Pi54rh protein and the presence of glycosylation, myristoylation and phosphorylation sites which implicates its role in signal transduction process. This is in contrast to other blast resistance genes that are predicted to be intracellular NBS-LRR-type resistance proteins. The Pi54rh was found to express constitutively at basal level in the leaves, but upregulates 3.8-fold at 96 h post-inoculation with the pathogen. Functional validation of cloned Pi54rh gene using complementation test showed high degree of resistance to seven isolates of M. oryzae collected from different geographical locations of India. In this study, for the first time, we demonstrated that a rice blast resistance gene Pi54rh cloned from wild species of rice provides broad spectrum resistance to M. oryzae hence can be used in rice improvement breeding programme.