First Author | Yamashita Y | Year | 1998 |
Journal | J Biochem | Volume | 123 |
Issue | 2 | Pages | 358-68 |
PubMed ID | 9538215 | Mgi Jnum | J:46479 |
Mgi Id | MGI:1201226 | Doi | 10.1093/oxfordjournals.jbchem.a021945 |
Citation | Yamashita Y, et al. (1998) Genomic structures and chromosomal location of p91, a novel murine regulatory receptor family. J Biochem 123(2):358-68 |
abstractText | Recently, we found a novel murine cell-surface glycoprotein, designated as p91, expressed mainly in myeloid cells such as macrophages and mast cells. The molecule has six immunoglobulin-like extracellular domains, a transmembrane segment, and a cytoplasmic tail containing four immunoreceptor tyrosine-based inhibition motif (ITIM) or ITIM-like sequences, resembling the structural features of human killer-cell inhibitory receptors (KIR). Here we show that p91 comprises a polymorphic gene family, harboring one potent inhibitory- type p91 and at least two other p91 genes. Tyrosine- phosphorylated, but not nonphosphorylated, synthetic peptides matching the third ITIM and the fourth ITIM-like sequences, respectively, found in the cytoplasmic portion of p91A, the sole inhibitory-type p91, were associated with the tyrosine phosphatases, SHP-1 and SHP-2. In addition, the phosphotyrosyl peptide matching the third ITIM sequence also bound the inositol B-phosphatase, SHIP. These results support the notion that p91A may function as an inhibitory cell-surface molecule against cell activation. The p91 genes were shown to be clustered in the proximal region of mouse chromosome 7, a syntenic position of human chromosome 19 where the genes for the KIR family are found. A human cDNA clone cross-hybridizing to a murine p91 probe was isolated from a human spleen cDNA library, and was found to code for a molecule quite similar to members of the immunoglobulin-like transcript (or ILT) family. The gene was found to be located on human chromosome 19q13.3-13.4. These results establish the existence of a novel set of potent regulatory receptors in mouse and man, similar but different from the KIR family. |