Genetic, physical, and transcript map of the Ltxs1 region of mouse chromosome 11

Lethal factor (LF) is a toxin secreted by Bacillus anthracis that plays an important role in the pathogenesis of anthrax. Intoxication with LF results in a macrophage-specific cytolysis that is not well understood. Interestingly, inbred mouse strains exhibit dramatic differences in the susceptibility of their cultured macrophages to killing by LF, and a gene that influences this phenotype, called Ltxs1, has been mapped to mouse chromosome 11. Here we report a high-resolution genetic map that confines the Ltxs1 region to a 0.51-cM interval between D11Mit90 and D11Die37/D11Die38. We have also constructed a complete physical map of YAC and BAC clones covering the Ltxs1 region. In conjunction with synteny homology searching, BLAST searches of sequences obtained from the clones in the physical map have revealed 14 known genes and five ESTs that reside in the critical interval. Additionally, a region of 100 kb or more is deleted in the Ltxs1 interval of some strains. Our genetic, physical, and transcript map provides an important resource for the molecular cloning of Ltxs1.