Three of the principal members of the pentraxin family are serum proteins: namely, CRP, SAP, and
hamster female protein (FP).
PTX3 (or TSG-14) protein is a
cytokine-induced protein that is
homologous to CRPs and SAPs.
C-reactive protein C-reactive protein is expressed during the
acute phase response to tissue injury or
inflammation in mammals. The protein resembles antibody and performs several functions associated with host defence: it promotes
agglutination, bacterial capsular swelling and
phagocytosis, and activates the
classical complement pathway through its calcium-dependent binding to
phosphocholine.
Serum amyloid P component Serum amyloid P component is a vertebrate protein that is identical to tissue forms of amyloid P component. It is found in all types of amyloid deposits, in
glomerular basement membrane and in
elastic fibres in
blood vessels. SAP binds to various
lipoprotein ligands in a calcium-dependent manner, and it has been suggested that, in mammals, this may have important implications in
atherosclerosis and
amyloidosis. NPTXI and NPTXII are homologous and can exist within one species. It is suggested that both proteins mediate the uptake of synaptic macromolecules and play a role in
synaptic plasticity.
Apexin, a sperm acrosomal protein, is a homologue of NPTXII found in
Cavia porcellus (Guinea pig).
Human Human genes encoding proteins that contain this domain include: •
APCS •
CRP •
GPR144 •
NPTX1;
NPTX2;
NPTXR •
PTX3 •
SVEP1 == References ==