scholarly journals A glycoprotein in the plasma membrane matrix as a major potential substrate of p60v-src.

1990 ◽  
Vol 10 (2) ◽  
pp. 830-836 ◽  
Author(s):  
M Hamaguchi ◽  
M Matsuda ◽  
H Hanafusa
Keyword(s):  
Plasma Membrane ◽  
Rous Sarcoma Virus ◽  
Transmembrane Protein ◽  
Temperature Sensitive ◽  
Morphological Transformation ◽  
Fibronectin Receptor ◽  
Rous Sarcoma ◽  
Sarcoma Virus ◽  
Potential Substrate ◽  
In Cells

A potential substrate of p60v-src in Rous sarcoma virus-transformed cells was found to be a 130-kilodalton (kDa) glycoprotein which binds to lectin-Sepharose and can be immunoprecipitated by an anti-phosphotyrosine antibody. This glycoprotein was shown to be distinct from the fibronectin receptor and a cellular protein phosphorylated in p60v-src immune complexes. The protein was a transmembrane protein localized in the plasma membrane and resistant to extraction with Triton X-100. The 130-kDa protein was also highly phosphorylated in cells transformed by Fujinami sarcoma virus or Y73 but not in cells infected with Rous sarcoma virus mutants that encode p60v-src lacking myristoylated N termini. Phosphorylation of this glycoprotein was temperature dependent in cells infected with temperature-sensitive mutants. The good correlation between its phosphorylation and morphological transformation, together with its relative abundance among phosphorylated proteins and its subcellular localization, suggests that phosphorylation of the 130-kDa glycoprotein is one of the primary events important for cell transformation by p60v-src and related oncogene products.

A glycoprotein in the plasma membrane matrix as a major potential substrate of p60v-src

1990 ◽  
Vol 10 (2) ◽  
pp. 830-836
Author(s):  
M Hamaguchi ◽  
M Matsuda ◽  
H Hanafusa
Keyword(s):  
Plasma Membrane ◽  
Rous Sarcoma Virus ◽  
Transmembrane Protein ◽  
Temperature Sensitive ◽  
Morphological Transformation ◽  
Fibronectin Receptor ◽  
Rous Sarcoma ◽  
Sarcoma Virus ◽  
Potential Substrate ◽  
In Cells

A potential substrate of p60v-src in Rous sarcoma virus-transformed cells was found to be a 130-kilodalton (kDa) glycoprotein which binds to lectin-Sepharose and can be immunoprecipitated by an anti-phosphotyrosine antibody. This glycoprotein was shown to be distinct from the fibronectin receptor and a cellular protein phosphorylated in p60v-src immune complexes. The protein was a transmembrane protein localized in the plasma membrane and resistant to extraction with Triton X-100. The 130-kDa protein was also highly phosphorylated in cells transformed by Fujinami sarcoma virus or Y73 but not in cells infected with Rous sarcoma virus mutants that encode p60v-src lacking myristoylated N termini. Phosphorylation of this glycoprotein was temperature dependent in cells infected with temperature-sensitive mutants. The good correlation between its phosphorylation and morphological transformation, together with its relative abundance among phosphorylated proteins and its subcellular localization, suggests that phosphorylation of the 130-kDa glycoprotein is one of the primary events important for cell transformation by p60v-src and related oncogene products.

scholarly journals Phosphorylation of cellular proteins in Rous sarcoma virus-infected cells: analysis by use of anti-phosphotyrosine antibodies.

1988 ◽  
Vol 8 (8) ◽  
pp. 3035-3042 ◽  
Author(s):  
M Hamaguchi ◽  
C Grandori ◽  
H Hanafusa
Keyword(s):  
Gel Electrophoresis ◽  
Rous Sarcoma Virus ◽  
Cellular Proteins ◽  
Morphological Transformation ◽  
Protein Substrates ◽  
Rous Sarcoma ◽  
Sarcoma Virus ◽  
Infected Cells ◽  
Avian Sarcoma ◽  
In Cells

The protein substrates for the tyrosine protein kinases in cells transformed by avian sarcoma viruses were analyzed by gel electrophoresis in combination with immunoblotting or immunoprecipitation by antibodies against phosphotyrosine. We found that greater than 90% of phosphotyrosine-containing cellular proteins can be immunoprecipitated by these antibodies. The level of phosphotyrosine-containing cellular proteins detectable by this method markedly increased upon transformation with Rous sarcoma virus, and more than 20 distinct bands of such proteins were found in lysates of Rous sarcoma virus-transformed cells. Most of these phosphotyrosine-containing proteins had not been identified by other methods, and their presence appeared to correlate with morphological transformation in cells infected with various Rous sarcoma virus mutants and Y73, PRCII, and Fujinami sarcoma viruses. However, considerably different patterns were obtained with cells infected with nontransforming Rous sarcoma virus mutants that encode nonmyristylated src kinases, indicating that most substrates that correlate with transformation can only be recognized by p60v-src associated with the plasma membrane.

Phosphorylation of talin at tyrosine in Rous sarcoma virus-transformed cells

1987 ◽  
Vol 7 (1) ◽  
pp. 371-378
Author(s):  
J E DeClue ◽  
G S Martin
Keyword(s):  
Rous Sarcoma Virus ◽  
Peptide Mapping ◽  
Temperature Sensitive ◽  
Permissive Temperature ◽  
Sensitive Mutant ◽  
Tyrosine Residues ◽  
Rous Sarcoma ◽  
Sarcoma Virus ◽  
Chicken Embryo Fibroblasts ◽  
In Cells

The cytoskeletal protein talin was found to undergo enhanced phosphorylation at tyrosine residues in chicken embryo fibroblasts following transformation by Rous sarcoma virus. An increase in the tyrosine phosphorylation of talin was also observed within 6 h in cells infected by the temperature-sensitive mutant tsNY68 after a shift from the nonpermissive to the permissive temperature. The overall extent of phosphorylation was 0.07 mol of phosphate per mol of talin and was not appreciably altered by transformation. In uninfected cells talin was shown to be phosphorylated at multiple sites by tryptic peptide mapping. Following transformation most of these sites remained phosphorylated, to the same or to a lesser extent, while novel, phosphotyrosine-containing phosphopeptides appeared. Talin was phosphorylated at tyrosine in cells infected by Rous sarcoma virus mutants which induce altered or partial transformation morphologies; thus the increased phosphorylation of talin at tyrosine occurred irrespective of the morphology induced. Transformation by Y73 also induced elevated levels of phosphotyrosine in talin, whereas transformation by the avian erythroblastosis and Fujinami sarcoma viruses did not.

Phosphorylation of cellular proteins in Rous sarcoma virus-infected cells: analysis by use of anti-phosphotyrosine antibodies

1988 ◽  
Vol 8 (8) ◽  
pp. 3035-3042
Author(s):  
M Hamaguchi ◽  
C Grandori ◽  
H Hanafusa
Keyword(s):  
Gel Electrophoresis ◽  
Rous Sarcoma Virus ◽  
Cellular Proteins ◽  
Morphological Transformation ◽  
Protein Substrates ◽  
Rous Sarcoma ◽  
Sarcoma Virus ◽  
Infected Cells ◽  
Avian Sarcoma ◽  
In Cells

The protein substrates for the tyrosine protein kinases in cells transformed by avian sarcoma viruses were analyzed by gel electrophoresis in combination with immunoblotting or immunoprecipitation by antibodies against phosphotyrosine. We found that greater than 90% of phosphotyrosine-containing cellular proteins can be immunoprecipitated by these antibodies. The level of phosphotyrosine-containing cellular proteins detectable by this method markedly increased upon transformation with Rous sarcoma virus, and more than 20 distinct bands of such proteins were found in lysates of Rous sarcoma virus-transformed cells. Most of these phosphotyrosine-containing proteins had not been identified by other methods, and their presence appeared to correlate with morphological transformation in cells infected with various Rous sarcoma virus mutants and Y73, PRCII, and Fujinami sarcoma viruses. However, considerably different patterns were obtained with cells infected with nontransforming Rous sarcoma virus mutants that encode nonmyristylated src kinases, indicating that most substrates that correlate with transformation can only be recognized by p60v-src associated with the plasma membrane.

scholarly journals Phosphorylation of talin at tyrosine in Rous sarcoma virus-transformed cells.

1987 ◽  
Vol 7 (1) ◽  
pp. 371-378 ◽  
Author(s):  
J E DeClue ◽  
G S Martin
Keyword(s):  
Rous Sarcoma Virus ◽  
Peptide Mapping ◽  
Temperature Sensitive ◽  
Permissive Temperature ◽  
Sensitive Mutant ◽  
Tyrosine Residues ◽  
Rous Sarcoma ◽  
Sarcoma Virus ◽  
Chicken Embryo Fibroblasts ◽  
In Cells

The cytoskeletal protein talin was found to undergo enhanced phosphorylation at tyrosine residues in chicken embryo fibroblasts following transformation by Rous sarcoma virus. An increase in the tyrosine phosphorylation of talin was also observed within 6 h in cells infected by the temperature-sensitive mutant tsNY68 after a shift from the nonpermissive to the permissive temperature. The overall extent of phosphorylation was 0.07 mol of phosphate per mol of talin and was not appreciably altered by transformation. In uninfected cells talin was shown to be phosphorylated at multiple sites by tryptic peptide mapping. Following transformation most of these sites remained phosphorylated, to the same or to a lesser extent, while novel, phosphotyrosine-containing phosphopeptides appeared. Talin was phosphorylated at tyrosine in cells infected by Rous sarcoma virus mutants which induce altered or partial transformation morphologies; thus the increased phosphorylation of talin at tyrosine occurred irrespective of the morphology induced. Transformation by Y73 also induced elevated levels of phosphotyrosine in talin, whereas transformation by the avian erythroblastosis and Fujinami sarcoma viruses did not.

Interaction between the Rous sarcoma virus transforming protein and two cellular phosphoproteins: analysis of the turnover and distribution of this complex

1983 ◽  
Vol 3 (1) ◽  
pp. 9-19
Author(s):  
J Brugge ◽  
W Yonemoto ◽  
D Darrow
Keyword(s):  
Rous Sarcoma Virus ◽  
Temperature Sensitive ◽  
Chase Period ◽  
Rous Sarcoma ◽  
Src Gene ◽  
Discrete Population ◽  
Sarcoma Virus ◽  
Transforming Activity ◽  
The Stability ◽  
In Cells

The transforming protein of Rous sarcoma virus (RSV), pp60src, was previously shown to associate with two cellular proteins of Mr 90,000 and 50,000 in RSV-transformed chicken cells. In this report, we demonstrate that this interaction is specific for a discrete population of pp60src molecules. Newly synthesized pp60src was found to preferentially associate with pp90 and pp50 to form a short-lived complex. The half-life of this complex varied from 9 to 15 min in cells transformed by nondefective strains of RSV. This interaction between pp60src, pp50, and pp90 took place in a soluble fraction of the cell, and the complex-bound pp60src molecules were not phosphorylated on tyrosine. These results suggest that pp90 and pp50 may be involved in the processing of pp60src molecules before the association of pp60src with the plasma membrane. The kinetics of dissociation of this complex were shown to be altered in cells infected with viruses containing a temperature-sensitive defect in the src gene. When cells infected with these viruses were grown at the nonpermissive temperature, more than 90% of the pp60src molecules were associated with pp90 and pp50, and little or no dissociation was observed in a 3-h chase period. These results suggest that mutations in the src gene which affect the transforming activity of pp60src also affect the stability of the interaction of pp60src with pp90 and pp50.

scholarly journals Interaction between the Rous sarcoma virus transforming protein and two cellular phosphoproteins: analysis of the turnover and distribution of this complex.

1983 ◽  
Vol 3 (1) ◽  
pp. 9-19 ◽  
Author(s):  
J Brugge ◽  
W Yonemoto ◽  
D Darrow
Keyword(s):  
Rous Sarcoma Virus ◽  
Temperature Sensitive ◽  
Chase Period ◽  
Rous Sarcoma ◽  
Src Gene ◽  
Discrete Population ◽  
Sarcoma Virus ◽  
Transforming Activity ◽  
The Stability ◽  
In Cells

The transforming protein of Rous sarcoma virus (RSV), pp60src, was previously shown to associate with two cellular proteins of Mr 90,000 and 50,000 in RSV-transformed chicken cells. In this report, we demonstrate that this interaction is specific for a discrete population of pp60src molecules. Newly synthesized pp60src was found to preferentially associate with pp90 and pp50 to form a short-lived complex. The half-life of this complex varied from 9 to 15 min in cells transformed by nondefective strains of RSV. This interaction between pp60src, pp50, and pp90 took place in a soluble fraction of the cell, and the complex-bound pp60src molecules were not phosphorylated on tyrosine. These results suggest that pp90 and pp50 may be involved in the processing of pp60src molecules before the association of pp60src with the plasma membrane. The kinetics of dissociation of this complex were shown to be altered in cells infected with viruses containing a temperature-sensitive defect in the src gene. When cells infected with these viruses were grown at the nonpermissive temperature, more than 90% of the pp60src molecules were associated with pp90 and pp50, and little or no dissociation was observed in a 3-h chase period. These results suggest that mutations in the src gene which affect the transforming activity of pp60src also affect the stability of the interaction of pp60src with pp90 and pp50.

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