Nerve growth factor-stimulated nuclear S6 kinase in PC12 cells.
Previous work has shown that nerve growth factor (NGF) stimulates the phosphorylation of the ribosomal protein S6 in PC12 cells. In this study, we show that S6 kinase activity is also present in purified PC12 cell nuclei. This activity was increased by treatment of the cells with NGF and, to a lesser extent, by treatment with epidermal growth factor. The NGF-stimulated activity was obtained from nuclear extracts and some of its characteristics described. The increase in activity was prevented by treatment of the cells with rapamycin or with wortmannin, and the overall activity could be precipitated by antibodies directed against the p85SGK. These data indicate that p85SGK is the NGF-stimulated S6 kinase in PC12 cell nuclei. The presence of S6 protein in the nucleus of PC12 cells has been confirmed and evidence is presented that suggests that it is identical to a protein called SMP reported some years ago.
Tang
T
T
Section on Growth Factors, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda 20892, USA.
Hirata
Y
Y
Whalin
M
M
Guroff
G
G
D000595:Amino Acid Sequence; D000730:Androstadienes / Q000494:pharmacology; D000818:Animals; D002467:Cell Nucleus / Q000201:enzymology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004815:Epidermal Growth Factor / Q000494:pharmacology; D007166:Immunosuppressive Agents / Q000494:pharmacology; D008969:Molecular Sequence Data; D009414:Nerve Growth Factors / Q000494:pharmacology*; D016716:PC12 Cells / Q000378:metabolism*; D010446:Peptide Fragments / Q000235:genetics; D011090:Polyenes / Q000494:pharmacology; D011233:Precipitin Tests; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D019893:Ribosomal Protein S6 Kinases; D020123:Sirolimus; D000077191:Wortmannin
D000730:Androstadienes; D004791:Enzyme Inhibitors; D007166:Immunosuppressive Agents; D009414:Nerve Growth Factors; D010446:Peptide Fragments; D011090:Polyenes; D004815:Epidermal Growth Factor; D017346:Protein Serine-Threonine Kinases; D019893:Ribosomal Protein S6 Kinases; D020123:Sirolimus; D000077191:Wortmannin