Changes in proteinase activities during the differentiation of murine erythroleukemia cells.
Changes in intracellular proteinase activities were examined during DMSO-induced differentiation of murine erythroleukemia cells. Suc-APA-MCA hydrolytic activity was significantly decreased, and apparent ATP-dependent multicatalytic proteinase activity was also decreased with MEL cell differentiation. Cathepsin B and L activity was mainly present in the microsomal fraction of control cells, but a part of this activity had shifted to the lysosomal fraction of differentiated cells. With the translocation of cathepsin B from the microsomal to the lysosomal fraction, the pro-enzyme form of cathepsin B was converted into the mature enzyme. These results suggest that the lysosomal pathway contributes to the degradation of specific proteins with cell differentiation.
National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan.
T
T
Tsukahara
S
S
Ishiura
E
E
Kominami
H
H
Sugita
D000818:Animals; D002471:Cell Transformation, Neoplastic / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D010450:Endopeptidases / Q000378:metabolism*; D004915:Leukemia, Erythroblastic, Acute / Q000201:enzymology* / Q000473:pathology; D008247:Lysosomes / Q000502:physiology; D051379:Mice; D013997:Time Factors; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism / Q000473:pathology
D010450:Endopeptidases; D004121:Dimethyl Sulfoxide