Neoplastic transformation induced by an activated lymphocyte-specific protein tyrosine kinase (pp56lck).

The lck proto-oncogene encodes a lymphocyte-specific member of the src family of protein tyrosine kinases. Here we demonstrate that pp56lck is phosphorylated in vivo at a carboxy-terminal tyrosine residue (Tyr-505) analogous to Tyr-527 of pp60c-src. Substitution of phenylalanine for tyrosine at this position resulted in increased phosphorylation of a second tyrosine residue (Tyr-394) and was associated with an increase in apparent kinase activity. In addition, this single point mutation unmasked the oncogenic potential of pp56lck in NIH 3T3 cell transformation assays. Viewed in the context of similar results obtained with pp60c-src, it is likely that the enzymatic activity and transforming ability of all src-family protein tyrosine kinases can be regulated by carboxy-terminal tyrosine phosphorylation. We further demonstrate that overexpression of pp56lck in the murine T-cell lymphoma LSTRA as a result of a retroviral insertion event produces a kinase protein that despite wild-type primary structure is nevertheless hypophosphorylated at Tyr-505. Thus, control of normal growth in this lymphoid cell line may have been abrogated through acquisition of a posttranslationally activated version of pp56lck.

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Conformationally Induced Off–On Cell Membrane Chemosensor Targeting Receptor Protein-Tyrosine Kinases for in Vivo and in Vitro Fluorescence Imaging of Cancers

Journal of the American Chemical Society ◽

10.1021/jacs.7b10796 ◽

2018 ◽

Vol 140 (18) ◽

pp. 5882-5885 ◽

Cited By ~ 27

Author(s):

Yang Jiao ◽

Jiqiu Yin ◽

Haiyang He ◽

Xiaojun Peng ◽

Qianmiao Gao ◽

...

Keyword(s):

Cell Membrane ◽

Fluorescence Imaging ◽

Tyrosine Kinases ◽

Protein Tyrosine Kinases ◽

Receptor Protein ◽

Protein Tyrosine ◽

Receptor Protein Tyrosine Kinases

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The Carboxy-Terminal Fragment of Nucleolin Interacts with the Nucleocapsid Domain of Retroviral Gag Proteins and Inhibits Virion Assembly

Journal of Virology ◽

10.1128/jvi.74.23.11027-11039.2000 ◽

2000 ◽

Vol 74 (23) ◽

pp. 11027-11039 ◽

Cited By ~ 36

Author(s):

Eran Bacharach ◽

Jason Gonsky ◽

Kimona Alin ◽

Marianna Orlova ◽

Stephen P. Goff

Keyword(s):

Leukemia Virus ◽

Single Point ◽

Host Protein ◽

Single Point Mutation ◽

Gag Protein ◽

Virion Assembly ◽

Gag Proteins ◽

Carboxy Terminal

ABSTRACT A yeast two-hybrid screen for cellular proteins that interact with the murine leukemia virus (MuLV) Gag protein resulted in the identification of nucleolin, a host protein known to function in ribosome assembly. The interacting fusions contained the carboxy-terminal 212 amino acids of nucleolin [Nuc(212)]. The nucleocapsid (NC) portion of Gag was necessary and sufficient to mediate the binding to Nuc(212). The interaction of Gag with Nuc(212) could be demonstrated in vitro and was manifested in vivo by the NC-dependent incorporation of Nuc(212) inside MuLV virions. Overexpression of Nuc(212), but not full-length nucleolin, potently and specifically blocked MuLV virion assembly and/or release. A mutant of MuLV, selected to specifically disrupt the binding to Nuc(212), was found to be severely defective for virion assembly. This mutant harbors a single point mutation in capsid (CA) adjacent to the CA-NC junction, suggesting a role for this region in Moloney MuLV assembly. These experiments demonstrate that selection for proteins that bind assembly domain(s) can yield potent inhibitors of virion assembly. These experiments also raise the possibility that a nucleolin-Gag interaction may be involved in virion assembly.

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Phospholipase C-γ is a substrate for the PDGF and EGF receptor protein-tyrosine kinases in vivo and in vitro

Cell ◽

10.1016/0092-8674(89)90048-2 ◽

1989 ◽

Vol 57 (7) ◽

pp. 1109-1122 ◽

Cited By ~ 582

Author(s):

Jill Meisenhelder ◽

Pann-Ghill Suh ◽

Sue Goo Rhee ◽

Tony Hunter

Keyword(s):

Phospholipase C ◽

Tyrosine Kinases ◽

Egf Receptor ◽

Protein Tyrosine Kinases ◽

Receptor Protein ◽

Protein Tyrosine ◽

Receptor Protein Tyrosine Kinases

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Novel yeast protein kinase (YPK1 gene product) is a 40-kilodalton phosphotyrosyl protein associated with protein-tyrosine kinase activity.

Molecular and Cellular Biology ◽

10.1128/mcb.10.12.6244 ◽

1990 ◽

Vol 10 (12) ◽

pp. 6244-6256 ◽

Cited By ~ 51

Author(s):

D Dailey ◽

G L Schieven ◽

M Y Lim ◽

H Marquardt ◽

T Gilmore ◽

...

Keyword(s):

Protein Kinase ◽

Tyrosine Kinase ◽

Tyrosine Kinases ◽

Protein Tyrosine Kinase ◽

Kinase Activity ◽

Protein Tyrosine Kinases ◽

Tyrosine Kinase Activity ◽

Protein Tyrosine ◽

Protein Tyrosine Kinase Activity

Extracts of bakers' yeast (Saccharomyces cerevisiae) contain protein-tyrosine kinase activity that can be detected with a synthetic Glu-Tyr copolymer as substrate (G. Schieven, J. Thorner, and G.S. Martin, Science 231:390-393, 1986). By using this assay in conjunction with ion-exchange and affinity chromatography, a soluble tyrosine kinase activity was purified over 8,000-fold from yeast extracts. The purified activity did not utilize typical substrates for mammalian protein-tyrosine kinases (enolase, casein, and histones). The level of tyrosine kinase activity at all steps of each preparation correlated with the content of a 40-kDa protein (p40). Upon incubation of the most highly purified fractions with Mn-ATP or Mg-ATP, p40 was the only protein phosphorylated on tyrosine. Immunoblotting of purified p40 or total yeast extracts with antiphosphotyrosine antibodies and phosphoamino acid analysis of 32P-labeled yeast proteins fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated that the 40-kDa protein is normally phosphorylated at tyrosine in vivo. 32P-labeled p40 immunoprecipitated from extracts of metabolically labeled cells by affinity-purified anti-p40 antibodies contained both phosphoserine and phosphotyrosine. The gene encoding p40 (YPK1) was cloned from a yeast genomic library by using oligonucleotide probes designed on the basis of the sequence of purified peptides. As deduced from the nucleotide sequence of YPK1, p40 is homologous to known protein kinases, with features that resemble known protein-serine kinases more than known protein-tyrosine kinases. Thus, p40 is a protein kinase which is phosphorylated in vivo and in vitro at both tyrosine and serine residues; it may be a novel type of autophosphorylating tyrosine kinase, a bifunctional (serine/tyrosine-specific) protein kinase, or a serine kinase that is a substrate for an associated tyrosine kinase.

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Tec protein-tyrosine kinase is involved in interleukin-3 signaling pathway

Blood ◽

10.1182/blood.v85.2.343.343 ◽

1995 ◽

Vol 85 (2) ◽

pp. 343-350 ◽

Cited By ~ 59

Author(s):

H Mano ◽

Y Yamashita ◽

K Sato ◽

Y Yazaki ◽

H Hirai

Keyword(s):

Signaling Pathway ◽

Cell Lines ◽

Tyrosine Kinases ◽

Protein Tyrosine Kinase ◽

Kinase Activity ◽

Protein Tyrosine Kinases ◽

Protein Tyrosine ◽

Interleukin 3 ◽

Hematopoietic Cell Lines

Abstract Among cytoplasmic protein-tyrosine kinases (PTKs) Tec now forms a novel subfamily with recently identified Tec-related PTKs (Btk and Itk/Tsk). Tec is known to be abundantly expressed in myeloid cells, and multiple forms of Tec protein can be generated via the mechanism of alternative splicing. In this report, we have investigated 5′-terminal diversity of the tec messages to demonstrate a predominant form of the Tec protein in mouse hematopoietic cell lines. Using anti-Tec serum, we could show that stimulation with interleukin-3 (IL-3) can induce tyrosine phosphorylation of Tec both in myeloid and pro-B-cell lines. IL-3 stimulation was also shown to induce kinase activity of Tec. Furthermore, we could demonstrate that Tec is constitutively associated with the Shc protein in vivo. Thus, we conclude that Tec is involved in the signaling pathway of IL-3.

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Novel yeast protein kinase (YPK1 gene product) is a 40-kilodalton phosphotyrosyl protein associated with protein-tyrosine kinase activity

Molecular and Cellular Biology ◽

10.1128/mcb.10.12.6244-6256.1990 ◽

1990 ◽

Vol 10 (12) ◽

pp. 6244-6256

Author(s):

D Dailey ◽

G L Schieven ◽

M Y Lim ◽

H Marquardt ◽

T Gilmore ◽

...

Keyword(s):

Protein Kinase ◽

Tyrosine Kinase ◽

Tyrosine Kinases ◽

Protein Tyrosine Kinase ◽

Kinase Activity ◽

Protein Tyrosine Kinases ◽

Tyrosine Kinase Activity ◽

Protein Tyrosine ◽

Protein Tyrosine Kinase Activity

Extracts of bakers' yeast (Saccharomyces cerevisiae) contain protein-tyrosine kinase activity that can be detected with a synthetic Glu-Tyr copolymer as substrate (G. Schieven, J. Thorner, and G.S. Martin, Science 231:390-393, 1986). By using this assay in conjunction with ion-exchange and affinity chromatography, a soluble tyrosine kinase activity was purified over 8,000-fold from yeast extracts. The purified activity did not utilize typical substrates for mammalian protein-tyrosine kinases (enolase, casein, and histones). The level of tyrosine kinase activity at all steps of each preparation correlated with the content of a 40-kDa protein (p40). Upon incubation of the most highly purified fractions with Mn-ATP or Mg-ATP, p40 was the only protein phosphorylated on tyrosine. Immunoblotting of purified p40 or total yeast extracts with antiphosphotyrosine antibodies and phosphoamino acid analysis of 32P-labeled yeast proteins fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated that the 40-kDa protein is normally phosphorylated at tyrosine in vivo. 32P-labeled p40 immunoprecipitated from extracts of metabolically labeled cells by affinity-purified anti-p40 antibodies contained both phosphoserine and phosphotyrosine. The gene encoding p40 (YPK1) was cloned from a yeast genomic library by using oligonucleotide probes designed on the basis of the sequence of purified peptides. As deduced from the nucleotide sequence of YPK1, p40 is homologous to known protein kinases, with features that resemble known protein-serine kinases more than known protein-tyrosine kinases. Thus, p40 is a protein kinase which is phosphorylated in vivo and in vitro at both tyrosine and serine residues; it may be a novel type of autophosphorylating tyrosine kinase, a bifunctional (serine/tyrosine-specific) protein kinase, or a serine kinase that is a substrate for an associated tyrosine kinase.

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Tec protein-tyrosine kinase is involved in interleukin-3 signaling pathway

Blood ◽

10.1182/blood.v85.2.343.bloodjournal852343 ◽

1995 ◽

Vol 85 (2) ◽

pp. 343-350 ◽

Cited By ~ 5

Author(s):

H Mano ◽

Y Yamashita ◽

K Sato ◽

Y Yazaki ◽

H Hirai

Keyword(s):

Signaling Pathway ◽

Cell Lines ◽

Tyrosine Kinases ◽

Protein Tyrosine Kinase ◽

Kinase Activity ◽

Protein Tyrosine Kinases ◽

Protein Tyrosine ◽

Interleukin 3 ◽

Hematopoietic Cell Lines

Among cytoplasmic protein-tyrosine kinases (PTKs) Tec now forms a novel subfamily with recently identified Tec-related PTKs (Btk and Itk/Tsk). Tec is known to be abundantly expressed in myeloid cells, and multiple forms of Tec protein can be generated via the mechanism of alternative splicing. In this report, we have investigated 5′-terminal diversity of the tec messages to demonstrate a predominant form of the Tec protein in mouse hematopoietic cell lines. Using anti-Tec serum, we could show that stimulation with interleukin-3 (IL-3) can induce tyrosine phosphorylation of Tec both in myeloid and pro-B-cell lines. IL-3 stimulation was also shown to induce kinase activity of Tec. Furthermore, we could demonstrate that Tec is constitutively associated with the Shc protein in vivo. Thus, we conclude that Tec is involved in the signaling pathway of IL-3.

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