Nck inhibits NGF and basic FGF induced PC12 cell differentiation via mitogen-activated protein kinase-independent pathway.
Proto-oncogene Nck, an adapter molecule containing three SH3 and one SH2 domains, binds to cell surface receptors and mediates mitogenic effects in the cells. Overexpression of Nck caused cell transformation in vitro and tumor formation in the nude mice. The mechanism of this action by Nck, however, remained unclear. Rat adrenal pheochromocytoma cell line PC12 provides a useful system for studying growth factor-regulated cell proliferation and differentiation. Serum and epidermal growth factor (EGF) stimulate proliferation, whereas nerve growth factor (NGF) and basic fibroblast growth factor (bFGF) cause growth arrest and sympathetic neurite outgrowth in these cells. To study the function of Nck, we generated stable clones of PC12 cells overexpressing the human Nck. We report here that the overexpressed Nck caused continued proliferation of PC12 cells even in the presence of NGF and blocked both the NGF- and bFGF-induced neurite outgrowth. Anti-sense but not sense oligonucleotides to the human Nck resumed the NGF-induced differentiation, indicating the specific inhibitory effect of Nck. Interestingly, Nck did not interfere with the kinetics of NGF- and EGF-stimulated protein tyrosine phosphorylation and the mitogen-activated protein kinase (MAPK) activation, suggesting that Nck inhibited the induced PC12 cell differentiation via a MAPK-independent mechanism. This study has provided a useful system for further understanding the function of Nck.
Rockow
S
S
The Ben May Institute, and Department of Pharmacological and Physiological Sciences, The University of Chicago, Illinois 60637, USA.
Tang
J
J
Xiong
W
W
Li
W
W
D048868:Adaptor Proteins, Signal Transducing; D000310:Adrenal Gland Neoplasms / Q000378:metabolism* / Q000473:pathology; D000818:Animals; D001483:Base Sequence; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D002455:Cell Division / Q000187:drug effects / Q000502:physiology*; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology*; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D008969:Molecular Sequence Data; D009414:Nerve Growth Factors / Q000494:pharmacology*; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D015513:Oncogene Proteins / Q000235:genetics / Q000502:physiology*; D016366:Open Reading Frames; D016716:PC12 Cells; D010673:Pheochromocytoma / Q000378:metabolism* / Q000473:pathology; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D000090063:Proto-Oncogene Mas; D051381:Rats
D048868:Adaptor Proteins, Signal Transducing; C000715470:MAS1 protein, human; C078332:Nck protein; D009414:Nerve Growth Factors; D016376:Oligonucleotides, Antisense; D015513:Oncogene Proteins; D000090063:Proto-Oncogene Mas; D016222:Fibroblast Growth Factor 2; D011505:Protein-Tyrosine Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases