CD47 [SEP] found in taxon
fibrosis.
CD47 is involved in a range of cellular processes, including apoptosis, proliferation, adhesion, and migration. Furthermore, it plays a key role in immune and angiogenic responses. CD47 is ubiquitously expressed in human cells and has been found to be overexpressed in many different tumor cells. Expression in equine cutaneous tumors has been reported as well.
Structure.
CD47 is a 50 kDa membrane receptor that has extracellular N-terminal IgV domain, five transmembrane domains, and a short C-terminal intracellular tail.
three Immunoglobulin superfamily domains – single V-set and two C1-set IgSF domains. SIRP β and γ have the similar extracellular structure but different cytoplasmic regions giving contrasting types of signals. SIRP α polymorphisms are found in ligand-binding IgSF V-set domain but it does not affect ligand binding. One idea is that the polymorphism is important to protect the receptor of pathogens binding.
Ligands.
SIRPα recognizes CD47, an anti-phagocytic signal that distinguishes live cells from dying cells. CD47 has a single Ig-like