title: Napsins: new human aspartic proteinases. Distinction between two closely related genes.
abstract: cDNA sequences were elucidated for two closely related human genes which encode the precursors of two hitherto unknown aspartic proteinases. The (pro)napsin A gene is expressed predominantly in lung and kidney and 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. The (pro)napsin B gene is transcribed exclusively in cells related to the immune system but lacks an in-frame stop codon and contains a number of polymorphisms, one of which replaces a catalytically crucial Gly residue with an Arg. Consideration is given to whether (pro)napsin B may be a transcribed pseudogene or whether its putative protein product undergoes rapid intracellular degradation.
authors.affiliation: School of Biosciences, Cardiff University, UK.
authors.forename: P J
authors.initials: PJ
authors.lastname: Tatnell
authors.forename: D J
authors.initials: DJ
authors.lastname: Powell
authors.forename: J
authors.initials: J
authors.lastname: Hill
authors.forename: T S
authors.initials: TS
authors.lastname: Smith
authors.forename: D G
authors.initials: DG
authors.lastname: Tew
authors.forename: J
authors.initials: J
authors.lastname: Kay
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016282:Aspartic Acid Endopeptidases / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D001483:Base Sequence; D002460:Cell Line; D004792:Enzyme Precursors / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D006031:Glycosylation; D006367:HeLa Cells; D006801:Humans; D007668:Kidney / Q000201:enzymology; D008168:Lung / Q000201:enzymology; D051379:Mice; D008969:Molecular Sequence Data; D009369:Neoplasms / Q000201:enzymology / Q000235:genetics; D009842:Oligopeptides; D009928:Organ Specificity; D020116:Pepsinogen A / Q000737:chemistry; D014176:Protein Biosynthesis; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D013552:Swine; D014407:Tumor Cells, Cultured
chemical_list: D004792:Enzyme Precursors; D009842:Oligopeptides; D011994:Recombinant Proteins; C047981:arginyl-glycyl-aspartic acid; D020116:Pepsinogen A; D016282:Aspartic Acid Endopeptidases