Napsins: new human aspartic proteinases. Distinction between two closely related genes.
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.
Tatnell
P J
PJ
School of Biosciences, Cardiff University, UK.
Powell
D J
DJ
Hill
J
J
Smith
T S
TS
Tew
D G
DG
Kay
J
J
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
D004792:Enzyme Precursors; D009842:Oligopeptides; D011994:Recombinant Proteins; C047981:arginyl-glycyl-aspartic acid; D020116:Pepsinogen A; D016282:Aspartic Acid Endopeptidases