METHODS OF USING THE NIM1 GENE TO CONFER DISEASE RESISTANCE IN PLANTS

摘要

The invention concerns the location and characterization of a gene (designated NIM1) that is a key component of the SAR pathway and that in connection with chemical and biological inducers enables induction of SAR gene expression and broad spectrum disease resistance in plants. The NIM1 gene product is a structural homologue of the mammalian signal transduction factor IλB subclass α. The present invention exploits this discovery to provide altered forms of NIM1 that act as dominant-negative regulators of the systemic acquired resistance (SAR) signal transduction pathway. These altered forms of NIM1 confer the opposite phenotype as the nim1 mutant in plants transformed with the altered forms of NIM1, i.e. the transgenic plants exhibit constitutive SAR gene expression and a constitutive immunity (CIM) phenotype. The invention further concerns transformation vectors and processes for overexpressing the NIM1 gene in plants. The transgenic plants thus created have broad spectrum disease resistance. The present invention further concerns DNA molecules encoding altered forms of the NIM1 gene, expression vectors containing such DNA molecules, and plants and plant cells transformed therewith. The invention further concerns transformation vectors and processes for overexpressing the NIM1 gene in plants. Disclosed are vectors and processes for producing overexpression of the NIM1 gene in plants. The invention also concerns methods of activating SAR in plants and conferring to plants a CIM phenotype and broad spectrum disease resistance by transforming the plants with DNA molecules encoding altered forms of the NIM1 gene product.