title: Cloning of a new lectin-like receptor expressed on human NK cells.
abstract: Natural killer (NK) cells constitute the third major population of lymphocytes. They possess the inherent capacity to kill various tumor and virally infected cells and mediate the rejection of bone-marrow grafts in lethally irradiated animals. A large family of NK cell receptors belong to the C-type lectin superfamily and are localized to the NK gene complex on Chromosome (Chr) 6 in the mouse and Chr 12 in the human. Genes in the NK gene complex encode type II receptors and examples include the families of NKR-P1, Ly-49, and NKG2 receptors. Examples of other C-type lectin-like NK cell receptors that occur as individual genes are CD94, CD69, and AICL. Here we report the molecular characterization and chromosomal mapping of a human lectin-like transcript (LLT1) expressed on NK, T, and B cells and localized to the NK gene complex within 100 kilobases of CD69. The cDNA encodes a predicted protein of 191 amino acid residues with a transmembrane domain near the N-terminus and an extracellular domain of 132 amino acid residues with similarity to the carbohydrate recognition domain of C-type lectins. The predicted protein of LLT1 shows 59 and 56% similarity to AICL and CD69, respectively. The predicted protein does not contain any intracellular ITIM motifs, suggesting that LLT1 may be involved in mediating activation signals.
authors.affiliation: Department of Molecular Biology and Immunology, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107-2699, USA.
authors.forename: K S
authors.initials: KS
authors.lastname: Boles
authors.forename: R
authors.initials: R
authors.lastname: Barten
authors.forename: P R
authors.initials: PR
authors.lastname: Kumaresan
authors.forename: J
authors.initials: J
authors.lastname: Trowsdale
authors.forename: P A
authors.initials: PA
authors.lastname: Mathew
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002874:Chromosome Mapping; D002881:Chromosomes, Human, Pair 12; D003001:Cloning, Molecular; D006801:Humans; D007694:Killer Cells, Natural; D037102:Lectins / Q000235:genetics*; D037181:Lectins, C-Type; D008214:Lymphocytes; D008969:Molecular Sequence Data; D011956:Receptors, Cell Surface / Q000235:genetics*; D017386:Sequence Homology, Amino Acid
chemical_list: C400041:CLEC2D protein, human; D037102:Lectins; D037181:Lectins, C-Type; D011956:Receptors, Cell Surface