Intracellular transport and processing of lysosomal cathepsin H.
Intracellular transport and processing of lysosomal cathepsin H was investigated in the subcellular fractions of rat liver by pulse-labeling experiments with [35S]methionine in vivo. A newly synthesized procathepsin H with a molecular weight of 41 kDa first appeared in the rough microsomal fraction at 10 min postinjection of label. This procathepsin H moved from the microsomal fraction to the Golgi subfractions at 30 min. Then a processed single-chain form with 28 kDa appeared in the lysosomal fraction at 60 min and persisted as the predominant form after 180 min. These results suggest that the propeptide-processing of procathepsin H indeed takes place in lysosomes in the course of intracellular transport from endoplasmic reticulum via Golgi complex to lysosomes.
Nishimura
Y
Y
Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.
Kato
K
K
D000818:Animals; D056655:Cathepsin H; D002403:Cathepsins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D003546:Cysteine Endopeptidases; D006056:Golgi Apparatus / Q000201:enzymology; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008247:Lysosomes / Q000201:enzymology*; D008297:Male; D008715:Methionine / Q000378:metabolism; D008862:Microsomes, Liver / Q000201:enzymology; D011499:Protein Processing, Post-Translational; D051381:Rats; D011919:Rats, Inbred Strains
D008715:Methionine; D002403:Cathepsins; D003546:Cysteine Endopeptidases; D056655:Cathepsin H; C534128:Ctsh protein, rat