[Intracellular distribution of proteasomes in A-431 cells].
The intracellular proteasome distribution in A-431 cells was shown using methods of cell fractionation and immunofluorescence. In growing cells the distribution of proteasomes was EGF-dependent. In unstimulated cells and within 30 min of EGF treatment, proteasomes were localized in the cytoplasm and nuclei, but not on the plasma membrane. After 30 min of EGF treatment they were observed on the plasma membrane as well. In A-431 cells cultivated for 24 h in the medium with a lowered serum concentration, proteasomes were detected on the plasma membrane already in unstimulated cells. It is suggested that dephosphorylation of the EGF receptor and signalling proteins in unstimulated cells may depend on the proteolytic activity of proteasomes.
Evdonin
A L
AL
Institute of Cytology, Russian Academy of Sciences, St. Petersburg.
Tsupkina
N V
NV
Konstantinova
I M
IM
Medvedeva
N D
ND
D002467:Cell Nucleus / Q000378:metabolism / Q000648:ultrastructure*; D003546:Cysteine Endopeptidases / Q000378:metabolism / Q000648:ultrastructure*; D003593:Cytoplasm / Q000378:metabolism / Q000648:ultrastructure*; D004815:Epidermal Growth Factor / Q000378:metabolism; D066246:ErbB Receptors / Q000378:metabolism; D006801:Humans; D009097:Multienzyme Complexes / Q000378:metabolism / Q000648:ultrastructure*; D046988:Proteasome Endopeptidase Complex; D014407:Tumor Cells, Cultured
D009097:Multienzyme Complexes; D004815:Epidermal Growth Factor; D066246:ErbB Receptors; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex
Vnutrikletochnoe raspredelenie proteasom v kletkakh A-431.