SIGLEC7
SIGLEC7 (sialic acid-binding Ig-like lectin 7, also known as SIGLEC-7, p75/AIRM1, QA79 and CD328) is a membrane lectin of the immunoglobulin superfamily that binds sialic acid. In the immune response it is thought to act as an inhibitory receptor, including on natural killer cells. Browse Assay Genie's current range of SIGLEC7 research reagents below, or read on for the biology behind the target.
SIGLEC7 is a putative adhesion molecule that mediates sialic-acid dependent binding to cells. It preferentially binds alpha-2,3- and alpha-2,6-linked sialic acid, and it also binds disialogangliosides, including disialogalactosyl globoside, disialyl lactotetraosylceramide and disialyl GalNAc lactotetraosylceramide. The sialic acid recognition site may be masked by cis interactions with sialic acids on the same cell surface.
In the immune response, SIGLEC7 may act as an inhibitory receptor. After ligand-induced tyrosine phosphorylation, it is proposed to recruit cytoplasmic phosphatases through their SH2 domains. These phosphatases block signal transduction by dephosphorylating signalling molecules. SIGLEC7 mediates inhibition of natural killer cell cytotoxicity. It may also play a role in haemopoiesis: in vitro, it inhibits differentiation of CD34+ cell precursors towards the myelomonocytic lineage and restrains proliferation of leukaemic myeloid cells.
The SIGLEC7 gene encodes a membrane protein that belongs to the immunoglobulin superfamily and the SIGLEC (sialic acid binding Ig-like lectin) family. Genome annotation predicts sialic acid binding activity, a role in cell adhesion and activity at the plasma membrane. HGNC places it in the CD molecules, V-set domain containing and sialic acid binding Ig like lectin gene groups. Earlier names and symbols include sialic acid binding Ig-like lectin 19 pseudogene, SIGLEC19P and SIGLECP2.
SIGLEC7 mediates inhibition of natural killer cell cytotoxicity, making it a focus for studies of how sialic acid recognition restrains NK cell activity.
Ligand-induced tyrosine phosphorylation may recruit SH2-domain phosphatases, so SIGLEC7 is used to study inhibitory signalling by dephosphorylation of signalling molecules.
SIGLEC7 binds alpha-2,3- and alpha-2,6-linked sialic acid and disialogangliosides, and cis interactions may mask its binding site.
In vitro, SIGLEC7 inhibits CD34+ precursor differentiation towards the myelomonocytic lineage and the proliferation of leukaemic myeloid cells.
SIGLEC7 is a sialic acid-binding lectin that mediates sialic-acid dependent binding to cells. In immune cells it may act as an inhibitory receptor, recruiting phosphatases after tyrosine phosphorylation, and it mediates inhibition of natural killer cell cytotoxicity.
Aliases include SIGLEC-7, p75/AIRM1, QA79 and CD328. Earlier HGNC names and symbols include sialic acid binding Ig-like lectin 19 pseudogene (SIGLEC19P) and sialic acid binding Ig-like lectin pseudogene 2 (SIGLECP2). The approved name is sialic acid binding Ig like lectin 7.
SIGLEC7 belongs to the immunoglobulin superfamily and the SIGLEC family of sialic acid binding Ig-like lectins. Related members with their own target pages include SIGLEC1, SIGLEC5, SIGLEC6, SIGLEC8, SIGLEC9, SIGLEC10, SIGLEC14 and SIGLEC15.
Other SIGLEC family sialic acid-binding lectins and immune receptors with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q9Y286; product specifications from Assay Genie datasheets.