Effects of epidermal growth factor on protein degradation the translocation of non-histone proteins to the nucleus and DNA synthesis.
Stimulation of resting Chang liver or monkey kidney cells, prelabeled with [3H]leucine, by epidermal growth factor (EGF), caused inhibition of cellular protein degradation and a parallel increase nuclear translocation of 3H-labeled non-histone proteins and DNA synthesis. Nuclear translocation of these proteins was independent of protein synthesis. Fractionation of the nuclear 3H-labeled non-histone proteins in a pH gradient of 2.5-6.5 showed that the protein fractions with a high degree of proteolysis in resting cells corresponded to the protein fractions with a high extent of translocation in stimulated cells, suggesting that degradation and translocation of these proteins may be related. EGF inhibited cellular uptake of [3H]chloroquine, suggesting that EGF inhibits non-histone protein degradation via the lysosomal pathway. These observations support the hypothesis that EGF induces non-histone protein translocation to the nucleus by inhibiting lysosomal degradation of these proteins.
Polet
H
H
Department of Pathology, University of Illinois, College of Medicine, Chicago, IL 60612.
Fryxell
D
D
D001692:Biological Transport / Q000187:drug effects; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D002738:Chloroquine / Q000378:metabolism; D004247:DNA / Q000096:biosynthesis*; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D006863:Hydrogen-Ion Concentration; D007668:Kidney / Q000378:metabolism / Q000648:ultrastructure; D007700:Kinetics; D008099:Liver / Q000378:metabolism / Q000648:ultrastructure; D008247:Lysosomes / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*
D009687:Nuclear Proteins; D011506:Proteins; D004815:Epidermal Growth Factor; D002738:Chloroquine; D004247:DNA