S. Whitham et al., THE PRODUCT OF THE TOBACCO MOSAIC-VIRUS RESISTANCE GENE-N - SIMILARITY TO TOLL AND THE INTERLEUKIN-1 RECEPTOR, Cell, 78(6), 1994, pp. 1101-1115
The products of plant disease resistance genes are postulated to recog
nize invading pathogens and rapidly trigger host defense responses. He
re we describe isolation of the resistance gene N of tobacco that medi
ates resistance to the viral pathogen tobacco mosaic virus (TMV). The
N gene was isolated by transposon tagging using the maize Activator tr
ansposon. A genomic DNA fragment containing the N gene conferred TMV r
esistance to TMV susceptible tobacco. Sequence analysis of the N gene
shows that it encodes a protein of 131.4 kDa with an amino-terminal do
main similar to that of the cytoplasmic domain of the Drosophila Toll
protein and the interleukin-1 receptor (IL-1R) in mammals, a nucleotid
e-binding site (NBS), and 4 imperfect leucine-rich repeats (LRR). The
sequence similarity of N, Toll, and IL-1 R suggests that N mediates ra
pid gene induction and TMV resistance through a Toll-IL-1-like pathway
.