Cloning of Clr, a new family of lectin-like genes localized between mouse NKrp1a and Cd69

We report the identification of a novel family of genes, named Clr, encodin g C-type lectin-like molecules, which maps in the natural killer (NK) gene complex (NKC) on mouse Chromosome 6. Genomic sequence analysis indicates th e presence of at least seven members between Nkrp1a and Cd69. By RT-PCR, at least three members of the family are expressed on interleukin-2-activated NK cells. Sequence analysis revealed complete open reading frames of 203-2 05 amino acids, with a carboxyl-terminal C-type lectin-like carbohydrate re cognition domain (CRD). The CRDs of the Clr proteins exhibit a significant degree of homology with the known NKC-encoded NK-cell receptors. However, a key cysteine usually present in the CRD is missing in the Clr proteins, su ggesting that their ligands and functions proteins, suggesting that their l igands and functions are distinct from other molecules encoded in the NKC.