Lysosomal acid phosphatase is transported via endosomes to lysosomes.
Involvement of endosomes in transport of newly synthesized acid phosphatase to lysosomes was investigated using the Golgi fraction (GF1 + 2), enriched in endosomes. The Golgi fraction (GF1 + 2) was prepared from the livers of rats given [35S]methionine and asialofetuin conjugated-horseradish peroxidase (HRP). Newly synthesized acid phosphatase in the endosomes containing internalized asialofetuin-HRP was measured as a loss of the detectable labeled enzyme after 3,3'-diaminobenzidine (DAB) and H2O2 reaction, due to formation of insoluble polymers which reduce protein antigenicity. With this procedure, acid phosphatase was all but undetectable in the Golgi fraction. Thus, newly synthesized acid phosphatase is apparently transported to lysosomes by endosomes.
Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.
Y
Y
Tanaka
S
S
Yano
K
K
Okada
T
T
Ishikawa
M
M
Himeno
K
K
Kato
D000135:Acid Phosphatase / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001212:Asialoglycoproteins; D002458:Cell Fractionation; D060748:Fetuins; D006056:Golgi Apparatus / Q000201:enzymology; D006735:Horseradish Peroxidase / Q000378:metabolism; D008099:Liver / Q000201:enzymology / Q000648:ultrastructure; D008247:Lysosomes / Q000201:enzymology*; D008297:Male; D008854:Microscopy, Electron; D015388:Organelles / Q000201:enzymology*; D011499:Protein Processing, Post-Translational; D051381:Rats; D011919:Rats, Inbred Strains; D000509:alpha-Fetoproteins / Q000378:metabolism
D001212:Asialoglycoproteins; D060748:Fetuins; D000509:alpha-Fetoproteins; C017029:asialofetuin; D006735:Horseradish Peroxidase; D000135:Acid Phosphatase