Effect of N-tosyl-L-phenylalanylchloromethyl ketone on tumor necrosis factor-alpha -induced NF-kappaB activation and apoptosis in U937 cell line / 华中科技大学学报(医学)(英德文版)
Journal of Huazhong University of Science and Technology (Medical Sciences)
;
(6): 569-571, 2004.
Article
in English
| WPRIM
| ID: wpr-336976
ABSTRACT
To investigate the effect of N-tosyl-L-phenylalanylchloromethyl ketone (TPCK) on tumor necrosis factor-alpha-induced NF-kappaB activation and apoptosis in U937 cell line, changes and subcellular localization of NF-kappaB/p65 and IkappaB-alpha were observed by fluorescencemicroscopy and expression and degradation of IkappaB-alpha by flow cytometry. The apoptosis of U937 cells was measured by flow cytometry and electrophoresis of DNA. Immunolfluorescence assay showed that NF-kappaB/p65, IkappaB-alpha only localized in cytoplasm. After TNF-alpha stimulation, p65 was localized only in nuclei, and IkappaB-alpha was only localized in cytoplasm and decreased. The changes of TNF-alpha stimulation were specifically inhibited by TPCK. Flow cytometry also revealed the downregulation of IkappaB-alpha protein during TNF-alpha-induced apoptosis and the down-regulation was specifically inhibited by TPCK. Flow cytometry also showed the apoptosis of U937 cells after TNF-alpha induction. DNA ladder can be detected in cells treated by TNF-alpha. It is concluded that degradation of IkappaB-alpha protein and NF-kappaB/p65 translocation occur during TNF-alpha-induced apoptosis of U937 cells, suggesting the activation of NF-kappaB TPCK-sensitive protease plays an important role in the degradation of IkappaB-alpha protein induced by TNF-alpha in U937 cells. TPCK sensitive protease also plays an important role in the apoptosis of U937 cells induced by TNF-alpha.
Full text:
Available
Index:
WPRIM (Western Pacific)
Main subject:
Pharmacology
/
Tosylphenylalanyl Chloromethyl Ketone
/
Protein Synthesis Inhibitors
/
NF-kappa B
/
Tumor Necrosis Factor-alpha
/
Apoptosis
/
U937 Cells
/
Transcription Factor RelA
/
Flow Cytometry
/
Metabolism
Limits:
Humans
Language:
English
Journal:
Journal of Huazhong University of Science and Technology (Medical Sciences)
Year:
2004
Type:
Article
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