Napsin-A is an aspartic proteinase that is encoded in humans by the NAPSAgene.[5] The name napsin comes from novel aspartic proteinase of the pepsin family.[6]
The activation peptide of an aspartic proteinase acts as an inhibitor of the active site. These peptide segments, or pro-parts, are deemed important for correct folding, targeting, and control of the activation of aspartic proteinase zymogens. The pronapsin A gene is expressed predominantly in lung and kidney. Its translation product is predicted to be a fully functional, glycosylated aspartic proteinase precursor containing an RGD motif and an additional 18 residues at its C-terminus.[5]
Cook M, Bühling F, Ansorge S, et al. (2002). "Pronapsin A and B gene expression in normal and malignant human lung and mononuclear blood cells". Biochim. Biophys. Acta. 1577 (1): 10–6. doi:10.1016/s0167-4781(02)00400-1. PMID12151090.
Innocenti M, Zucconi A, Disanza A, et al. (2004). "Abi1 is essential for the formation and activation of a WAVE2 signalling complex". Nat. Cell Biol. 6 (4): 319–27. doi:10.1038/ncb1105. PMID15048123. S2CID22767022.