scholarly journals B-raf, a new member of the raf family, is activated by DNA rearrangement.

1988 ◽  
Vol 8 (6) ◽  
pp. 2651-2654 ◽  
Author(s):  
S Ikawa ◽  
M Fukui ◽  
Y Ueyama ◽  
N Tamaoki ◽  
T Yamamoto ◽  
...  
Keyword(s):  
Ewing Sarcoma ◽  
Dna Rearrangement ◽  
Terminal Portion ◽  
3T3 Cells ◽  
Complementary Dna ◽  
Amino Terminal ◽  
Transforming Activity ◽  
Nih 3T3 ◽  
Transforming Gene ◽  
Nih 3T3 Cells

Complementary DNA clones of a putative transforming gene were isolated from NIH 3T3 cells transformed with human Ewing sarcoma DNA. The gene was termed B-raf because it is related to but distinct from c-raf and A-raf. It appears that substitution in the amino-terminal portion of the normal B-raf protein confers transforming activity to the gene.

B-raf, a new member of the raf family, is activated by DNA rearrangement

1988 ◽  
Vol 8 (6) ◽  
pp. 2651-2654
Author(s):  
S Ikawa ◽  
M Fukui ◽  
Y Ueyama ◽  
N Tamaoki ◽  
T Yamamoto ◽  
...  
Keyword(s):  
Ewing Sarcoma ◽  
Dna Rearrangement ◽  
Terminal Portion ◽  
3T3 Cells ◽  
Complementary Dna ◽  
Amino Terminal ◽  
Transforming Activity ◽  
Nih 3T3 ◽  
Transforming Gene ◽  
Nih 3T3 Cells

Complementary DNA clones of a putative transforming gene were isolated from NIH 3T3 cells transformed with human Ewing sarcoma DNA. The gene was termed B-raf because it is related to but distinct from c-raf and A-raf. It appears that substitution in the amino-terminal portion of the normal B-raf protein confers transforming activity to the gene.

Loss of the amino-terminal helix-loop-helix domain of the vav proto-oncogene activates its transforming potential

1991 ◽  
Vol 11 (4) ◽  
pp. 1912-1920
Author(s):  
S Katzav ◽  
J L Cleveland ◽  
H E Heslop ◽  
D Pulido
Keyword(s):  
Leucine Zipper ◽  
Ectopic Expression ◽  
Cdna Clones ◽  
3T3 Cells ◽  
Amino Terminal ◽  
Helix Loop Helix ◽  
Transforming Activity ◽  
Nih 3T3 ◽  
Nih 3T3 Cells

vav, a novel human oncogene, was originally generated in vitro by replacement of its normal 5' coding sequences with sequences from pSV2neo DNA, cotransfected as a selectable marker (S. Katzav, D. Martin-Zanca, and M. Barbacid, EMBO J. 8:2283-2290, 1989). The vav proto-oncogene is normally expressed in cells of hematopoietic origin. To determine whether the 5' rearrangement of vav or its ectopic expression in NIH 3T3 cells contributes to its transforming potential, we isolated murine and human proto-vav cDNA clones as well as human genomic clones corresponding to the 5' end of the gene. Normal proto-vav was poorly transforming in NIH 3T3 cells, whereas truncation of its 5' end greatly enhanced its transforming activity. The relative failure of full-length proto-vav cDNA clones to transform NIH 3T3 cells indicates that the transforming activity of vav is not simply due to ectopic expression. Analysis of the predicted amino terminus of the vav proto-oncogene shows that it contains a helix-loop-helix domain and a leucine zipper motif similar to that of myc family proteins, though it lacks a basic region that is usually found adjacent to helix-loop-helix domains. Loss of the helix-loop-helix domain of proto-vav, either by truncation or by rearrangement with pSV2neo sequences, activates its oncogenic potential.

scholarly journals Loss of the amino-terminal helix-loop-helix domain of the vav proto-oncogene activates its transforming potential.

1991 ◽  
Vol 11 (4) ◽  
pp. 1912-1920 ◽  
Author(s):  
S Katzav ◽  
J L Cleveland ◽  
H E Heslop ◽  
D Pulido
Keyword(s):  
Leucine Zipper ◽  
Ectopic Expression ◽  
Cdna Clones ◽  
3T3 Cells ◽  
Amino Terminal ◽  
Helix Loop Helix ◽  
Transforming Activity ◽  
Nih 3T3 ◽  
Nih 3T3 Cells

vav, a novel human oncogene, was originally generated in vitro by replacement of its normal 5' coding sequences with sequences from pSV2neo DNA, cotransfected as a selectable marker (S. Katzav, D. Martin-Zanca, and M. Barbacid, EMBO J. 8:2283-2290, 1989). The vav proto-oncogene is normally expressed in cells of hematopoietic origin. To determine whether the 5' rearrangement of vav or its ectopic expression in NIH 3T3 cells contributes to its transforming potential, we isolated murine and human proto-vav cDNA clones as well as human genomic clones corresponding to the 5' end of the gene. Normal proto-vav was poorly transforming in NIH 3T3 cells, whereas truncation of its 5' end greatly enhanced its transforming activity. The relative failure of full-length proto-vav cDNA clones to transform NIH 3T3 cells indicates that the transforming activity of vav is not simply due to ectopic expression. Analysis of the predicted amino terminus of the vav proto-oncogene shows that it contains a helix-loop-helix domain and a leucine zipper motif similar to that of myc family proteins, though it lacks a basic region that is usually found adjacent to helix-loop-helix domains. Loss of the helix-loop-helix domain of proto-vav, either by truncation or by rearrangement with pSV2neo sequences, activates its oncogenic potential.

Specific activation of the cellular Harvey-ras oncogene in dimethylbenzanthracene-induced mouse mammary tumors

1986 ◽  
Vol 6 (11) ◽  
pp. 4104-4108
Author(s):  
S Dandekar ◽  
S Sukumar ◽  
H Zarbl ◽  
L J Young ◽  
R D Cardiff
Keyword(s):  
Mammary Tumors ◽  
3T3 Cells ◽  
Mouse Mammary Tumor ◽  
Mouse Mammary Tumors ◽  
Transforming Activity ◽  
Radiation Induced ◽  
Genomic Dnas ◽  
Nih 3T3 ◽  
Adenosine Nucleotide ◽  
Nih 3T3 Cells

Genomic DNAs from dimethylbenzanthracene-induced BALB/c mouse mammary tumors arising from the transplantable hyperplastic outgrowth (HPO) line designated DI/UCD transformed NIH 3T3 cells upon transfection. Transforming activity was attributed to the presence of activated Harvey ras-1 oncogenes containing an A----T transversion at the middle adenosine nucleotide in codon 61. DNAs from untreated DI/UCD HPO cells and radiation-induced and spontaneous mammary tumors from the DI/UCD HPO line failed to transform NIH 3T3 cells. The results indicated that the mutation activation of Harvey ras-1 oncogenes was specific to dimethylbenzanthracene treatment in the mouse mammary tumor system.

scholarly journals A transforming activity not detected by DNA transfer to NIH 3T3 cells is detected by JB6 mouse epidermal cells.

1985 ◽  
Vol 5 (4) ◽  
pp. 890-893 ◽  
Author(s):  
N H Colburn ◽  
M I Lerman ◽  
G A Hegamyer ◽  
T D Gindhart
Keyword(s):  
Tumor Cell ◽  
Cell Lines ◽  
Tumor Cell Lines ◽  
3T3 Cells ◽  
Anchorage Independence ◽  
Transforming Activity ◽  
Mouse Epidermal Cell ◽  
Nih 3T3 ◽  
Transforming Genes ◽  
Nih 3T3 Cells

Transfection of four different mouse epidermal tumor cell DNAs into NIH 3T3 cells yielded neither morphologically altered foci nor anchorage independence. However, promotion-sensitive, but not promotion-insensitive, JB6 mouse epidermal cell lines were permissive for the expression of anchorage independence after transfection of DNA from three of these tumor cell lines. This transforming activity and the promotion-sensitive activity that confers sensitivity to promotion of transformation show differences in restriction enzyme sensitivity. In view of this difference and the differences in both recipient cells and 12-O-tetradecanoyl-phorbol-13-acetate dependence of expression, it appears that the transforming activity and the promotion-sensitive activity are specified by different genes. The JB6 promotion-sensitive cell lines may be useful for detecting and cloning transforming genes that escape detection in the NIH 3T3 cell focus assay.

scholarly journals Mechanism of activation of the ret proto-oncogene by multiple endocrine neoplasia 2A mutations.

1995 ◽  
Vol 15 (3) ◽  
pp. 1613-1619 ◽  
Author(s):  
N Asai ◽  
T Iwashita ◽  
M Matsuyama ◽  
M Takahashi
Keyword(s):  
Cell Surface ◽  
Multiple Endocrine Neoplasia ◽  
Simian Virus 40 ◽  
Simian Virus ◽  
3T3 Cells ◽  
Endocrine Neoplasia ◽  
Transforming Activity ◽  
Nih 3T3 ◽  
Men 2A ◽  
Nih 3T3 Cells

Transforming activity of the c-ret proto-oncogene with multiple endocrine neoplasia (MEN) 2A mutations was investigated by transfection of NIH 3T3 cells. Mutant c-ret genes driven by the simian virus 40 or cytomegalovirus promoter induced transformation with high efficiencies. The 170-kDa Ret protein present on the cell surface of transformed cells was highly phosphorylated on tyrosine and formed disulfide-linked homodimers. This result indicated that MEN 2A mutations induced ligand-independent dimerization of the c-Ret protein on the cell surface, leading to activation of its intrinsic tyrosine kinase. In addition to the MEN 2A mutations, we further introduced a mutation (lysine for asparaginic acid at codon 300 [D300K]) in a putative Ca(2+)-binding site of the cadherin-like domain. When c-ret cDNA with both MEN 2A and D300K mutations was transfected into NIH 3T3 cells, transforming activity drastically decreased. Western blot (immunoblot) analysis revealed that very little of the 170-kDa Ret protein with the D300K mutation was expressed in transfectants while expression of the 150-kDa Ret protein retained in the endoplasmic reticulum was not affected. This result also demonstrated that transport of the Ret protein to the plasma membrane is required for its transforming activity.

Potent transforming activity of the small GTP-binding protein Rit in NIH 3T3 cells: evidence for a role of a p38γ-dependent signaling pathway

FEBS Letters ◽  
2001 ◽  
Vol 511 (1-3) ◽  
pp. 15-20 ◽  
Author(s):  
Kaoru Sakabe ◽  
Hidemi Teramoto ◽  
Muriel Zohar ◽  
Babak Behbahani ◽  
Hiroshi Miyazaki ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Binding Protein ◽  
3T3 Cells ◽  
Gtp Binding Protein ◽  
Gtp Binding ◽  
Transforming Activity ◽  
Nih 3T3 ◽  
Dependent Signaling Pathway ◽  
Nih 3T3 Cells

scholarly journals Apoptosis Induced by Rac GTPase Correlates with Induction of FasL and Ceramides Production

2000 ◽  
Vol 11 (12) ◽  
pp. 4347-4358 ◽  
Author(s):  
Nieves Embade ◽  
Pilar F. Valerón ◽  
Salvador Aznar ◽  
Eduardo López-Collazo ◽  
Juan Carlos Lacal
Keyword(s):  
De Novo ◽  
Simultaneous Increase ◽  
Parental Cell Line ◽  
Rho Proteins ◽  
3T3 Cells ◽  
Signaling Mechanism ◽  
Mitochondria Membrane Potential ◽  
Amino Terminal ◽  
Nih 3T3 ◽  
Nih 3T3 Cells

Rho proteins, members of the Ras superfamily of GTPases, are critical elements in signal transduction pathways governing cell proliferation and cell death. Different members of the family of human Rho GTPases, including RhoA, RhoC, and Rac1, participate in the regulation of apoptosis in response to cytokines and serum deprivation in different cell systems. Here, we have characterized the mechanism of apoptosis induced by Rac1 in NIH 3T3 cells. It requires protein synthesis and caspase-3 activity, but it is independent of the release of cytochrome c from mitochondria. Moreover, an increase in mitochondria membrane potential and the production of reactive oxygen species was observed. Rac1-induced apoptosis was related to the simultaneous increase in ceramide production and synthesis of FasL. Generation of FasL may be mediated by transcriptional regulation involving both c-Jun amino terminal kinase as well as nuclear factor-κB-dependent signals. None of these signals, ceramides or FasL, was sufficient to induce apoptosis in the parental cell line, NIH 3T3 cells. However, any of them was sufficient to induce apoptosis in the Rac1-expressing cells. Finally, inhibition of FasL signaling drastically reduced apoptosis by Rac1. Thus, Rac1 seems to induce apoptosis by a complex mechanism involving the generation of ceramides and the de novo synthesis of FasL. These results suggest that apoptosis mediated by Rac1 results from a signaling mechanism that involves biochemical and transcriptional events under control of Rac1.

Sign in / Sign up

Export Citation Format

Share Document