Alternative titles; symbols
HGNC Approved Gene Symbol: CLEC2D
Cytogenetic location: 12p13.31 Genomic coordinates (GRCh38) : 12:9,669,713-9,699,553 (from NCBI)
Some C-type lectin proteins (e.g., CD69; 107273) are used as receptors by natural killer (NK) cells and are encoded on chromosome 12. By searching an EST database with human and mouse NK receptor sequences as probes, followed by PCR and screening an NK cell cDNA library, Boles et al. (1999) obtained a cDNA encoding LLT1 (lectin-like transcript-1). The deduced 191-amino acid type II receptor protein contains 2 putative N-linked glycosylation sites, a single transmembrane domain, and a 30-amino acid intracellular domain. Northern blot analysis detected 5-, 3.5-, 2-, and 0.9-kb transcripts in peripheral blood, lymph node, thymus, spleen, and an NK cell line. Expression was weak in other hemopoietic cell lines, and no expression was detected in bone marrow or fetal liver. Southern blot analysis indicated that LLT1 is most likely a single-copy gene.
Aldemir et al. (2005) found that LLT1 bound to cells expressing CD161 (KLRB1; 602890). Expression of LLT1 in various NK-cell targets rapidly reduced CD161 surface expression, protected the targets from NK-mediated lysis, and inhibited IFNG (147570) production. Anti-CD161 alone failed to stimulate T-cell secretion of IFNG, but anti-CD161 together with anti-CD3 (see 186740) enhanced IFNG production compared with anti-CD3 alone. Aldemir et al. (2005) concluded that LLT1 is a ligand for CD161 and that their interaction differentially regulates NK- and T-cell functions. Rosen et al. (2005) presented similar findings.
By PAC analysis, Boles et al. (1999) mapped the LLT1 gene to 12p13 within 100 kb of CD69 in the NK gene complex.
Aldemir, H., Prod'homme, V., Dumaurier, M.-J., Retiere, C., Poupon, G., Cazareth, J., Bihl, F., Braud, V. M. Cutting edge: lectin-like transcript 1 is a ligand for the CD161 receptor. J. Immun. 176: 7791-7795, 2005.
Boles, K. S., Barten, R., Kumaresan, P. R., Trowsdale, J., Mathew, P. A. Cloning of a new lectin-like receptor expressed on human NK cells. Immunogenetics 50: 1-7, 1999. [PubMed: 10541800] [Full Text: https://doi.org/10.1007/s002510050679]
Rosen, D. B., Bettadapura, J., Alsharifi, M., Mathew, P. A., Warren, H. S., Lanier, L. L. Cutting edge: lectin-like transcript-1 is a ligand for the inhibitory human NKR-P1A receptor. J. Immun. 176: 7796-7799, 2005.