Figure 3

Three NB-LRR genes (NLR-A, NLR-B, and NLR-C) located in the OSR locus. (a) Graphical genotypes of RIL lines showing recombination at the putative OSR region on chromosome 5. OSR was mapped within a 743-kb region between SNP markers Chr05:7,971,429 and Chr05:8,714,734. The gray, striped, and black bars represent chromosomal regions homozygous for BTx623, heterozygous, and homozygous for NOG, respectively. ‘R’ and ‘S’ indicates lines resistant and sensitive to fenitrothion, respectively. (b) A closeup view of the putative OSR locus, located near SNP marker Chr05:8,666,663. Gray, red, blue, and green arrows indicate the positions of the UDP-glucoronosyl transferase gene, NLR-A, NLR-B, and NLR-C, respectively. The smaller black arrows indicate the relative location of primers used to amplify NLR-A in (c). The dashed line indicates the missing region from 8,457,439 to 8,557,269 including NLR-A in NOG. The green arrowhead indicates the 593-bp insertion upstream of NLR-C in NOG. (c) Agarose gel electrophoresis of PCR products corresponding to NLR-A, showing that NOG lacks this gene. The original image of the gel is provided in Supplementary Information 2. (d) Schematic diagrams showing the presumed coiled-coil (CC), nucleotide binding site (NB), and leucine-rich repeat (LRR) domains in NLR-B (upper) and NLR-C (lower) proteins. Predicted amino acid substitutions in NOG, compared with those in BTx623, are indicated.