carboxypeptidase Z (CPZ)

Function

• cleaves substrates with C-terminal arginine residues
• modulates Wnt signaling pathway, by cleaving some undetermined protein (probable)
• role in cleavage during prohormone processing.

Cofactor: bind 1 Zn+2 per subunit

Inhibition:

• 2-mercaptomethyl-3-guanidinoethylthiopropanoic acid (MGTA)
• guanidinoethylmercaptosuccinic acid (GEMSA)
• chelating agents, including EDTA & EGTA

Kinetic parameters:

• KM=2 mM for dansyl-Phe-Ala-Arg;
• KM=2 mM for dansyl-Pro-Ala-Arg;
• Optimum pH is 7.8

Structure

• belongs to the peptidase M14 family
• contains 1 FZ (frizzled) domain

Compartment

secreted protein, extracellular matrix

Alternative splicing

named isoforms=2

Expression

• widely expressed
• placenta, present within invasive trophoblasts & in surrounding extracellular space
• present in amnion cells
• present in pituitary

More general terms

• carboxypeptidase
• glycoprotein
• metalloprotein
• matrix protein

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=8532
• OMIM: https://mirror.omim.org/entry/603105
• UniProt: http://www.uniprot.org/uniprot/Q66K79.html