PZP
PZP (pregnancy zone protein, also known as CPAMD6) is a secreted member of the alpha-2-macroglobulin family that inhibits proteinases by physically trapping them. It is highly expressed in late-pregnancy serum and is structurally similar to alpha-2-macroglobulin. Browse Assay Genie's current range of PZP research reagents below, or read on for the biology behind the target.
PZP is able to inhibit all four classes of proteinases through a 'trapping' mechanism. The protein carries a peptide stretch known as the bait region, which contains specific cleavage sites for different proteinases. When a proteinase cleaves the bait region, a conformational change is induced that traps the enzyme. The entrapped proteinase remains active against low molecular weight substrates, but its activity against high molecular weight substrates is greatly reduced. After cleavage in the bait region, a thioester bond is hydrolysed and mediates covalent binding of the protein to the proteinase.
The PZP gene encodes a secreted protein that acts as a homotetramer. It belongs to the protease inhibitor I39 (alpha-2-macroglobulin) family, and HGNC places it in the alpha-2-macroglobulin family gene group. The gene symbol stands for 'PZP alpha-2-macroglobulin like', and CPAMD6 is a recorded alias. Mouse and rat orthologs are listed as Pzp and A1m respectively, which is useful to bear in mind when designing cross-species studies.
The name reflects the protein's high expression in late-pregnancy serum, where it was first noted for its resemblance to alpha-2-macroglobulin. According to the NCBI Gene summary, PZP also appears to be elevated in the sera of presymptomatic Alzheimer's disease patients, which has made it a point of interest in studies of serum protein changes. Researchers working on PZP protein levels, proteinase regulation or pregnancy-associated serum proteins will find it a distinctive member of its family.
PZP traps proteinases from all four classes via its bait region, making it a model for broad-spectrum, conformational-change-driven protease inhibition.
PZP is highly expressed in late-pregnancy serum, so it is relevant to research on how circulating proteins change during gestation.
PZP appears to be elevated in the sera of presymptomatic Alzheimer's disease patients, prompting interest in it as a candidate serum marker.
Its structural similarity to alpha-2-macroglobulin makes PZP useful for comparing thioester-mediated proteinase capture across family members.
PZP is a secreted proteinase inhibitor. Proteinases cleave its bait region, which triggers a conformational change that traps the enzyme. A thioester bond is then hydrolysed and mediates covalent binding to the proteinase. It can inhibit all four classes of proteinases.
PZP stands for pregnancy zone protein, and its HGNC name is 'PZP alpha-2-macroglobulin like'. CPAMD6 is a recorded alias, and earlier names include pregnancy-zone protein. The encoded protein acts as a homotetramer.
The NCBI Gene summary notes that PZP appears elevated in the sera of presymptomatic Alzheimer's disease patients. Orthologs are listed as Pzp in mouse and A1m in rat; check the datasheet of any product for its validated reactivity.
Other alpha-2-macroglobulin family members, proteinase inhibitors and Alzheimer's disease-related targets with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P20742; product specifications from Assay Genie datasheets.