Carboxypeptidase N catalytic chain is an enzyme that in humans is encoded by the CPN1gene.
Carboxypeptidase N is a plasma metallo-protease that cleaves basic amino acids from the C terminal of peptides and proteins. The enzyme is important in the regulation of peptides like kinins and anaphylatoxins, and has also been known as kininase-1 and anaphylatoxin inactivator. This enzyme is a tetramer composed of two identical regulatory subunits and two identical catalytic subunits; this gene encodes the catalytic subunit. Mutations in this gene can be associated with angioedema or chronic urticaria resulting from carboxypeptidase N deficiency.
In melanocytic cells CPN1 gene expression may be regulated by MITF.
^Riley DA, Tan F, Miletich DJ, Skidgel RA (Apr 1999). "Chromosomal localization of the genes for human carboxypeptidase D (CPD) and the active 50-kilodalton subunit of human carboxypeptidase N (CPN1)". Genomics50 (1): 105–8. doi:10.1006/geno.1998.5295. PMID9628828.
Skidgel RA, Bennett CD, Schilling JW; et al. (1988). "Amino acid sequence of the N-terminus and selected tryptic peptides of the active subunit of human plasma carboxypeptidase N: comparison with other carboxypeptidases.". Biochem. Biophys. Res. Commun.154 (3): 1323–9. doi:10.1016/0006-291X(88)90284-7. PMID3408501.
Sato T, Miwa T, Akatsu H; et al. (2000). "Pro-carboxypeptidase R is an acute phase protein in the mouse, whereas carboxypeptidase N is not.". J. Immunol.165 (2): 1053–8. doi:10.4049/jimmunol.165.2.1053. PMID10878383.