An essential role for NOD1 in host recognition of bacterial peptidoglycan containing diaminopimelic acid.

Nucleotide-binding oligomerization domain protein 1 (NOD1) belongs to a family that includes multiple members with NOD and leucine-rich repeats in vertebrates and plants. NOD1 has been suggested to have a role in innate immune responses, but the mechanism involved remains unknown. Here we report that NOD1 mediates the recognition of peptidoglycan derived primarily from Gram-negative bacteria.

Genetic variation and activity of mouse Nod2, a susceptibility gene for Crohn's disease.

Genetic variation in human Nod2 has been associated with susceptibility to Crohn's disease. The mouse Nod2 locus is located at chromosome 8 and composed of 12 exons, 11 of which encode the Nod2 protein. Sequence analysis of Nod2 from 45 different strains of Mus musculus and Mus spretus revealed extensive polymorphism involving all exons of Nod2.

Crohn's disease-associated NOD2 variants share a signaling defect in response to lipopolysaccharide and peptidoglycan.

Background & Aims: The NOD2 variants R702W, G908R, and L1007fsinsC are strongly associated with Crohn's disease (CD) in both European and American populations, but whether this susceptibility extends to all ethnic groups remains unknown. Except for the L1007fsinsC mutation, which produces a truncated NOD2 protein, the functional activity of the major CD-associated variants G908R and R702W is unknown.

Methods: Individuals were genotyped for R702W, G908R, and L1007fsinsC.