| abstract |
The cell death response known as the hypersensitive response (HR) is a central feature of gene-for-gene plant disease resistance. Plants also defend against pathogens via multigenically controlled broad-spectrum defense responses, such as those modulated by salicylic acid. The DND (Defense, No Death) loci of Arabidopsis thaliana regulate the extent of broad-spectrum disease resistance against a broad range of viral, bacterial, oomycete and fungal pathogens. Plants lacking a functional copy of the DND1 or 2 gene are defective in HR cell death but exhibit successful gene-for-gene disease resistance. Plants lacking a functional copy of the DND1 or 2 gene also exhibit an enhanced broad-spectrum disease resistance phenotype. The DND1 and 2 gene products are identical to previously known cDNAs termed AtCNGC2 and 1, respectively, that encode apparent cyclic nucleotide-gated ion channel proteins. The identification of the CNGC/DND genes as regulators of disease resistance and host cell death, and the availability of CNGC/DND gene sequence information, provide new possibilities for controlling a wide variety of plant diseases. |