Effect of a dominant inhibitory Ha-ras mutation on mitogenic signal transduction in NIH 3T3 cells.

We used a dominant inhibitory mutation of c-Ha-ras which changes Ser-17 to Asn-17 in the gene product p21 [p21(Asn-17)Ha-ras] to investigate ras function in mitogenic signal transduction. An NIH 3T3 cell line [NIH(M17)] was isolated that displayed inducible expression of the mutant Ha-ras gene (Ha-ras Asn-17) via the mouse mammary tumor virus long terminal repeat and was growth inhibited by dexamethasone. The effect of dexamethasone induction on response of quiescent NIH(M17) cells to mitogens was then analyzed. Stimulation of DNA synthesis by epidermal growth factor (EGF) and 12-O-tetradecanoylphorbol-13-acetate (TPA) was completely blocked by p21(Asn-17) expression, and stimulation by serum, fibroblast growth factor, and platelet-derived growth factor was partially inhibited. However, the induction of fos, jun, and myc by EGF and TPA was not significantly inhibited in this cell line. An effect of p21(Asn-17) on fos induction was, however, demonstrated in transient expression assays in which quiescent NIH 3T3 cells were cotransfected with a fos-cat receptor plasmid plus a Ha-ras Asn-17 expression vector. In this assay, p21(Asn-17) inhibited chloramphenicol acetyltransferase expression induced by EGF and other growth factors. In contrast to its effect on DNA synthesis, however, Ha-ras Asn-17 expression did not inhibit fos-cat expression induced by TPA. Conversely, downregulation of protein kinase C did not inhibit fos-cat induction by activated ras or other oncogenes. These results suggest that ras proteins are involved in at least two parallel mitogenic signal transduction pathways, one of which is independent of protein kinase C. Although either pathway alone appears to be sufficient to induce fos, both appear to be necessary to induce the full mitogenic response.

Download Full-text

Genistein but not staurosporine can inhibit the mitogenic signal evoked by lithium in rat thyroid cells (FRTL-5)

Journal of Endocrinology ◽

10.1677/joe.0.1430221 ◽

1994 ◽

Vol 143 (2) ◽

pp. 221-226 ◽

Cited By ~ 10

Author(s):

T Takano ◽

K Takada ◽

H Tada ◽

S Nishiyama ◽

N Amino

Keyword(s):

Signal Transduction ◽

Protein Kinase C ◽

Protein Kinase ◽

Tyrosine Kinase ◽

Dna Synthesis ◽

Thyroid Cells ◽

Kinase C ◽

Mitogenic Signal Transduction ◽

Rat Thyroid ◽

Mitogenic Signal

Abstract Long-term administration of lithium is one of the well-known causes of goiter. It can stimulate DNA synthesis in rat thyroid cells (FRTL-5) treated with thyroid-stimulating hormone (TSH). To investigate the mitogenic signal transduction system activated by lithium, lithium-induced DNA synthesis and Ca2+ influx were studied using two protein kinase inhibitors, genistein as a specific tyrosine kinase inhibitor and staurosporine as a potent inhibitor of protein kinase C. Genistein but not staurosporine blocked the DNA synthesis induced by lithium in TSH-primed cells but neither compound had any effect on the Ca2+ entry stimulated by lithium. Genistein clearly attenuated the phosphotyrosine content of the 175 kDa substrate in the presence of lithium but staurosporine failed to do so. Moreover, lithium could also stimulate DNA synthesis in protein kinase C down-regulated cells. These data demonstrate that lithium may require the activation of a particular genistein-sensitive kinase, possibly a tyrosine kinase, to induce cell proliferation. It is suggested that the phorbol ester-sensitive protein kinase C family might not participate in the mitogenic signal transduction pathway activated by lithium. Journal of Endocrinology (1994) 143, 221–226

Download Full-text

Protein kinase C ζ isoform is critical for mitogenic signal transduction

Cell ◽

10.1016/0092-8674(93)80056-k ◽

1993 ◽

Vol 74 (3) ◽

pp. 555-563 ◽

Cited By ~ 273

Author(s):

Edurne Berra ◽

Maria T. Diaz-Meco ◽

Isabel Dominguez ◽

Maria M. Municio ◽

Laura Sanz ◽

...

Keyword(s):

Signal Transduction ◽

Protein Kinase C ◽

Protein Kinase ◽

Kinase C ◽

Mitogenic Signal Transduction ◽

Mitogenic Signal

Download Full-text

Mitogenic signaling pathways of growth factors can be distinguished by the involvement of pertussis toxin-sensitive guanosine triphosphate-binding protein and of protein kinase C.

Cell Regulation ◽

10.1091/mbc.1.10.747 ◽

1990 ◽

Vol 1 (10) ◽

pp. 747-761 ◽

Cited By ~ 20

Author(s):

N Nishizawa ◽

Y Okano ◽

Y Chatani ◽

F Amano ◽

E Tanaka ◽

...

Keyword(s):

Signal Transduction ◽

Protein Kinase C ◽

Growth Factors ◽

Growth Factor ◽

Protein Kinase ◽

Dna Synthesis ◽

Signaling Pathways ◽

Pertussis Toxin ◽

Guanosine Triphosphate ◽

Kinase C

We have examined the possible involvements of pertussis toxin (PT)-sensitive guanosine triphosphate (GTP)-binding protein (Gp) and protein kinase C (PKC) in the mitogenic signaling pathways of various growth factors by the use of PT-pretreated and/or 12-O-tetradecanoyl phorbol-13-acetate (TPA)-pretreated mouse fibroblasts. Effects of PT pretreatment (inactivation of PT-sensitive Gp) and TPA pretreatment (depletion of PKC) on mitogen-induced DNA synthesis varied significantly and systematically in response to growth factors: mitogenic responses of cells to thrombin, bombesin, and bradykinin were almost completely abolished both in PT- and TPA-pretreated cells; responses to epidermal growth factor (EGF), platelet-derived growth factor (PDGF), and vanadate were reduced to approximately 50% both in PT- and TPA-pretreated cells compared with native cells; response to basic fibroblast growth factor (bFGF) was not affected in PT-pretreated cells but was inhibited to some extent in TPA-pretreated cells. Thus, growth factors examined have been classified into three groups with regard to the involvements of PT-sensitive Gp and PKC in their signal transduction pathways. Binding of each growth factor to its receptor was not affected significantly by pretreatment of cells with PT or TPA. Inhibitory effects of PT and TPA pretreatment on each mitogen-induced DNA synthesis were not additive, suggesting that the functions of PT-sensitive Gp and PKC lie on an identical signal transduction pathway. Although all three groups of mitogens activated PKC, signaling of each growth factor depends to a varying extent on the function of PKC. Our results indicate that a single peptide growth factor such as EGF, PDGF, or bFGF acts through multiple signaling pathways to induce cell proliferation.

Download Full-text

Oncogenic and Activated Wild-Type ras-p21 Proteins Induce Different Isoforms of Protein Kinase C in Mitogenic Signal Transduction

Journal of Protein Chemistry ◽

10.1023/b:jopc.0000008727.46554.9e ◽

2003 ◽

Vol 22 (7/8) ◽

pp. 625-629 ◽

Cited By ~ 1

Author(s):

Lyndon Chie ◽

Yongxia Qu ◽

Denise Chung ◽

Mohammed Boutjdir ◽

Matthew R. Pincus

Keyword(s):

Signal Transduction ◽

Protein Kinase C ◽

Protein Kinase ◽

Wild Type ◽

Kinase C ◽

Ras P21 ◽

Mitogenic Signal Transduction ◽

P21 Proteins ◽

Mitogenic Signal

Download Full-text

Role of nuclear protein kinase C in the mitogenic response to platelet-derived growth factor

Journal of Cell Science ◽

10.1242/jcs.96.1.107 ◽

1990 ◽

Vol 96 (1) ◽

pp. 107-114

Author(s):

A.P. Fields ◽

G. Tyler ◽

A.S. Kraft ◽

W.S. May

Keyword(s):

Protein Kinase C ◽

Growth Factor ◽

Protein Kinase ◽

Nuclear Envelope ◽

Platelet Derived Growth Factor ◽

3T3 Cells ◽

Mitogenic Response ◽

3T3 Fibroblasts ◽

Kinase C ◽

Nih 3T3

We have assessed the involvement of nuclear envelope protein phosphorylation in the mitogenic response to platelet-derived growth factor (PDGF) in NIH/3T3 fibroblasts. We find that stimulation of quiescent NIH/3T3 cells with PDGF or with the mitogenic protein kinase C (PKC) activators phorbol 12-myristate 13-acetate (PMA) or bryostatin 1 (bryo) leads to rapid, dose-dependent phosphorylation of several nuclear envelope polypeptides. The predominant nuclear envelope targets for mitogen-induced phosphorylation are immunologically identified as the nuclear envelope lamins. All three lamin species (A, B and C) are phosphorylated in response to PMA or bryo, while lamins A and C are preferentially phosphorylated in response to PDGF. Phosphopeptide mapping and phosphoamino acid analysis indicate that similar serine sites on the lamins are phosphorylated in response to PDGF, PMA and bryo. Both mitogenicity and lamina phosphorylation induced by these mitogens can be inhibited by the selective PKC inhibitor staurosporine at 2 nM. Treatment of quiescent NIH/3T3 cells with PDGF, PMA or bryo leads to rapid translocation of PKC to the nuclear envelope. These data indicate that rapid nuclear events, including translocation of cytosolic PKC to the nuclear membrane and lamina phosphorylation, may play a role in the transduction of the mitogenic signals of PDGF from the cytoplasm to the nucleus in NIH/3T3 fibroblasts.

Download Full-text