|CD172a||SIRPα (signal regulatory protein α), SHPS-1|
|Molecule Type||Antigen Expression||Molecular Weight|
Min / Max
|Non-lineage Restricted Molecule|
Type 1 glycoprotein
Hematopoietic Progenitor Cell
|85 / 85|
90 / 90
|CD172a is expressed on CD34+ hematopoietic precursors stem/progenitor cells, neuronal tissue, macrophages, monocytes, granulocytes, dendritic cells. It is also expressed in the central nervous system on neurons in the hippocampus, cortex, striatum, cerebellar Purkinje cells and retina. Expression is ubiquitous, high in the brain, on myeloid cells but not on T cells. Expression is found in low levels in heart, placenta, lung, testis, ovary, colon, liver, small intestine, prostate, spleen, kidney, skeletal muscle and pancreas.|
|MOLECULAR FAMILY NAME: Belongs to the immunoglobulin gene superfamily.|
CD172α is a single-pass type-1 503 aa transmembrane glycoprotein. It contains a secretory signal sequence, an extracellular domain which contains 2 Ig-like C1-type domains and 1 Ig-like V-type domain, 4 potential N-linked glycosylation sites, several potential O-linked glycosylation sites, a putative transmembrane domain which contains a positively charged residue that interacts with the ITIM-containing DAP12/KARAP adaptor which is itself a transmembrane protein and an 100 aa long cytoplasmic domain with 2 ITIM motifs and a C-terminal proline-rich region. The ITIMs are phosphorylated on its tyrosine residue and associates with SHP-1 and SHP-2 phosphates which can bind when they are activated. CD172α is a member of the Ig superfamily, a subgroup of Ig-ITIM and a member of the signal regulatory protein (SIRP).
Alternative splicing yields 3 different isoforms.
POST-TRANSLATIONAL MODIFICATION: No information.
|LIGANDS AND MOLECULES ASSOCIATED WITH CD172a |
CD172α binds CD47 and the lung surfactant proteins SP-A and SP-D.
|CD172α is an adhesion and signal transduction molecule and is known to be involved in negative regulation of receptor tyrosine kinase-coupled signaling processes. These processes include suppression of anchorage-independent cell growth, negative regulation of immune cells, self-recognition of erythrocytes, mediation of macrophage multinucleation, skeletal muscle differentiation, entrainment of circadian clock, neuronal survival and synaptogenesis. CD47 has been demonstrated to be the ligand for CD172a which binds to CD47 (also known as integrin associated protein-IAP) and may mediate inhibitory signals via the ITIM/SHP-2. CD47 binding prevents maturation of immature dendritic cells and inhibits cytokine production by mature dendritic cells. |
BIOCHEMICAL ACTIVITY: No information.
DISEASE RELEVANCE AND FUNCTION OF CD172a IN INTACT ANIMAL: No information.
PROTEINS AND DNA ELEMENTS WHICH REGULATE TRANSCRIPTION OF CD172α: No information
SUBSTRATES: No information.
ENZYMES WHICH MODIFY CD172α: No information.
Database accession numbers
Revised June 25, 2008