Recombinant Human CD33 protein (Tagged)

Specifications

Form

Liquid

General info

Function

Sialic-acid-binding immunoglobulin-like lectin (Siglec) that plays a role in mediating cell-cell interactions and in maintaining immune cells in a resting state (PubMed : 10611343, PubMed : 11320212, PubMed : 15597323). Preferentially recognizes and binds alpha-2,3- and more avidly alpha-2,6-linked sialic acid-bearing glycans (PubMed : 7718872). Upon engagement of ligands such as C1q or syalylated glycoproteins, two immunoreceptor tyrosine-based inhibitory motifs (ITIMs) located in CD33 cytoplasmic tail are phosphorylated by Src-like kinases such as LCK (PubMed : 10887109, PubMed : 28325905). These phosphorylations provide docking sites for the recruitment and activation of protein-tyrosine phosphatases PTPN6/SHP-1 and PTPN11/SHP-2 (PubMed : 10206955, PubMed : 10556798, PubMed : 10887109). In turn, these phosphatases regulate downstream pathways through dephosphorylation of signaling molecules (PubMed : 10206955, PubMed : 10887109). One of the repressive effect of CD33 on monocyte activation requires phosphoinositide 3-kinase/PI3K (PubMed : 15597323).

Sequence similarities

Belongs to the immunoglobulin superfamily. SIGLEC (sialic acid binding Ig-like lectin) family.

Post-translational modifications

Glycosylated. Glycosylation at Asn-100 is critical for regulating ligand recognition.. Phosphorylation of Tyr-340 is involved in binding to PTPN6 and PTPN11. Phosphorylation of Tyr-358 is involved in binding to PTPN6. LCK phosphorylates Tyr-340 efficiently and Tyr-358 to a lesser extent.

Subcellular localisation

Peroxisome