Molecular cloning of human cathepsin G: structural similarity to mast cell and cytotoxic T lymphocyte proteinases.
Human cathepsin G is a serine proteinase with chymotrypsin-like specificity found in both polymorphonuclear leukocytes (neutrophils) and the U937 leukemic cell line. Utilizing RNA from the latter, we have constructed a cDNA library in lambda gt11 and isolated a clone which apparently codes for the complete amino acid sequence of this enzyme. Analysis of the sequence reveals homology with rat mast cell proteinase II (47%) but a greater degree of identity (56%) with a product of activated mouse cytotoxic T lymphocytes. The close relationship between the three proteins indicates similarities in substrate specificity and in biosynthesis which we predict involves removal of a two amino acid activation peptide during or just before packaging into their respective storage granules.
Salvesen
G
G
Farley
D
D
Shuman
J
J
Przybyla
A
A
Reilly
C
C
Travis
J
J
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D056649:Cathepsin G; D002403:Cathepsins / Q000235:genetics*; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA / Q000378:metabolism; D005796:Genes; D006801:Humans; D008407:Mast Cells / Q000201:enzymology*; D009504:Neutrophils / Q000201:enzymology*; D010447:Peptide Hydrolases / Q000235:genetics*; D051381:Rats; D012689:Sequence Homology, Nucleic Acid; D012697:Serine Endopeptidases; D013602:T-Lymphocytes, Cytotoxic / Q000201:enzymology*
D004247:DNA; D002403:Cathepsins; D010447:Peptide Hydrolases; D012697:Serine Endopeptidases; C534094:CTSG protein, human; D056649:Cathepsin G; C534096:Ctsg protein, mouse; C534097:Ctsg protein, rat