| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Chk and Lyn , but not Csk and c Src , co fractionated in the higher density lysate fractions of resting platelets , with Chk being found to localize close to CD 36 ( membrane glycoprotein 4 ) anchored Lyn . ^^^ Chk / Hyl is a recently isolated non receptor tyrosine kinase with greatest homology to a ubiquitous negative regulator of Src family kinases , Csk . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| We previously reported a novel human non receptor tyrosine kinase gene , HYL ( hematopoietic consensus tyrosine lacking kinase ) ( Sakano et al . , 1994 ) , which consists of each of the SH 2 ( src homology 2 ) , SH 3 and tyrosine kinase catalytic domains . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Like p50csk , Chk reduced the elevated phosphotyrosine levels and the augmented activity of Src family kinases in Csk deficient fibroblasts . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| The Csk homologous kinase ( CHK ) , formerly MATK , is a tyrosine kinase that contains the Src homology 2 and 3 ( SH 2 and SH 3 ) domains and demonstrates homology ( approximately 50 % ) to the Csk tyrosine kinase . ^^^ Like Csk , CHK is able to phosphorylate and inactivate Src family kinases . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| The Csk homologous kinase ( CHK ) is a recently identified tyrosine kinase which , like Csk , phosphorylates the C terminal tyrosine of Src kinases , resulting in inactivation of these enzymes . ^^^ Moreover , CHK was able to down regulate ErbB 2 / neu activated Src kinases . ^^^ These studies indicate that CHK binds , via its SH 2 domain , to Tyr 1253 of the activated ErbB 2 / neu and down regulates the ErbB 2 / neu mediated activation of Src kinases , thereby inhibiting breast cancer cell growth . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| The Csk homologous kinase ( Chk ) , which is co expressed with C terminal Src kinase ( Csk ) in hematopoietic cells , negatively regulates Src family kinases in vitro with selectivity toward Lyn but not c Src in platelets . ^^^ To explore the role of Src family kinases in hematopoietic cell adhesion , we overexpressed Chk in the megakaryocytic cell line Dami and established clones exhibiting a 10 fold increase in the amount of Chk . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Some of these molecules are themselves cytoplasmic tyrosine kinases such as the Src kinases , TEC , and CHK . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Binding assays and far Western blotting analysis , using glutathione S transferase fusion proteins containing the Src homology 2 ( SH 2 ) and SH 3 domains of CHK , demonstrate that the SH 2 domain of CHK binds directly to the tyrosine phosphorylated TrkA receptors . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| The Csk Homologous Kinase ( CHK ) has been shown to have an enzymatic activity similar to the tyrosine kinase Csk in that it down regulates Src family kinase activity by causing phosphorylation of the Src C terminal tyrosine residue . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| In vitro kinase assays showed that Chk overexpression suppressed the tyrosine kinase activity of Lyn , a member of the Src family , immunoprecipitated from Triton 10 100 lysates . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Furthermore , CHK down regulated c Src and Lyn protein expression and kinase activity , and the entry into mitosis was delayed in the wt CHK transfected MCF 7 cells upon HRG treatment . ^^^ We have previously shown that CHK associates with the ErbB 2 / neu receptor upon HRG stimulation via its SH 2 domain and that it down regulates the ErbB 2 / neu activated Src kinases . ^^^ These results indicate that CHK , but not Csk , is involved in HRG mediated signaling pathways , down regulates ErbB 2 / neu activated Src kinases , and inhibits invasion and transformation of breast cancer cells upon HRG stimulation . ^^^ These findings strongly suggest that CHK is a novel negative growth regulator of HRG mediated ErbB 2 / neu and Src family kinase signaling pathways in breast cancer cells . . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| CSK family contains two protein tyrosine kinases : Csk ( C terminal Src kinase ) and Chk ( Csk homologous kinase ) . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Although C terminal Src kinase ( CSK ) homologous kinase ( CHK ) is generally believed to inactivate Src family tyrosine kinases ( SFKs ) by phosphorylating their consensus C terminal regulatory tyrosine ( Tyr ( T ) ) , exactly how CHK inactivates SFKs is not fully understood . ^^^ First , CHK directly binds to the SFK members Hck , Lyn , and Src to form stable protein complexes . ^^^ Third , CHK and Src co localize to specific plasma membrane microdomains of rat brain cells , suggesting that CHK is in close proximity to Src such that it can effectively inactivate Src in vivo . ^^^ Src complex exists in rat brain , and recombinant CHK . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Furthermore , studies from our group indicate that the Csk homologous kinase ( CHK ) , a member of the Csk family , directly associates with HER2 / Neu and down regulates HER2 / Neu mediated Src kinase activation in breast cancer cells upon heregulin stimulation . ^^^ Since activation of RAFTK is associated with the activity of Src family kinases , we analyzed whether CHK is capable of opposing HRG induced activation of RAFTK . ^^^ This interaction was mediated through the Src binding site ( amino acid residue at 402 ) of RAFTK and the SH 2 domain of CHK . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Our previous studies demonstrated that Csk homologous kinase ( CHK ) acts as a negative growth regulator of human breast cancer through inhibition of ErbB 2 / neu mediated Src family kinase activity ( Bougeret , C . , Jiang , S . , Keydar , I . , and Avraham , H . ( 2001 ) J . ^^^ In this report , we investigated whether the interaction of the CHK SH 2 domain and ErbB 2 is directly related to the inhibition of heregulin stimulated Src kinase activity . ^^^ Furthermore , inhibition of heregulin stimulated Src kinase activity was markedly diminished by R147A , whereas G129R mediated inhibition was stronger as compared with wild type CHK . ^^^ These new CHK high affinity binding constructs may serve as good candidates for inhibition of the ErbB 2 / Src transduction pathway in gene therapy studies in breast cancer . . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| In the present study , we investigated the effect of overexpressing the Csk homologous kinase ( CHK ) , an inhibitor of Src family kinases , on the phosphorylation of Akt induced by two different factors : heregulin or cisplatin . ^^^ We observed that in MCF 7 CHK ( wt ) cells Lyn kinase activity was more profoundly inhibited than Src kinase activity . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Tyr 568 has previously been identified as the binding site of the Src family of tyrosine kinases , the Csk homologous kinase CHK , and the protein tyrosine phosphatase SHP 2 . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| BACKGROUND : Substantial evidence supports the suggestion that carboxyl terminal Src kinase ( Csk ) and Csk homologous kinase ( CHK ) , two negative regulatory kinases of the Src tyrosine kinase family , play distinct roles during development of the central nervous system ( CNS ) . ^^^ The authors observed an increase in CHK expression and a decline in Csk expression during differentiation of primary hippocampal neurons , but no difference in Src expression levels . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Using microarray gene analysis , we found that carboxyl terminal Src kinase homologous kinase ( CHK ) regulated the expression of the chemokine receptor , CXCR 4 . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Functional diversity of Csk , Chk , and Src SH 2 domains due to a single residue variation . ^^^ The C terminal Src kinase ( Csk ) family of protein tyrosine kinases contains two members : Csk and Csk homologous kinase ( Chk ) . ^^^ Recent reports suggest that the Src homology ( SH ) 2 domains of Csk and Chk may bind to different phosphoproteins , which provides a basis for different cellular functions for Csk and Chk . ^^^ To verify and characterize such a functional divergence , we compared the binding properties of the Csk , Chk , and Src SH 2 domains and investigated the structural basis for the functional divergence . ^^^ First , the study demonstrated striking functional differences between the Csk and Chk SH 2 domains and revealed functional similarities between the Chk and Src SH 2 domains . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Csk homologous kinase ( CHK ) , unlike Csk , enhances MAPK activation via Ras mediated signaling in a Src independent manner . ^^^ Substantial evidence exists supporting the notion that Csk and CHK , two negative regulatory kinases of the Src tyrosine kinase family , play distinct roles during development of the nervous system . ^^^ CHK inhibited Src activity following stimulation of the cells with NGF . ^^^ However , stimulation of Erk1 / 2 activation by CHK was independent of the NGF stimulation or the inhibition of Src kinase by CHK . ^^^ Taken together , this study describes for the first time the Src independent actions of CHK and provides novel insights into CHK function in neural cells . . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| The catalytic inhibitors include C terminal Src kinase ( CSK ) and CSK homologous kinase ( CHK ) that phosphorylate Y ( T ) of SFKs , as well as the protein tyrosine phosphatases that dephosphorylate pY ( A ) of the activated SFKs . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| C terminal Src kinase ( CSK ) and CSK homologous kinase ( CHK ) endogenous negative regulators of Src family protein kinases . ^^^ C terminal Src kinase ( CSK ) and CSK homologous kinase ( CHK ) are endogenous inhibitors of the Src family protein tyrosine kinases ( SFKs ) . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Molecular cloning of lsk , a carboxyl terminal src kinase ( csk ) related gene , expressed in leukocytes . ^^^ Because of its limited expression and high homology to p50csk , we named this gene lsk ; leukocyte carboxyl terminal src kinase related gene . ^^^ Identification of a molecule like lsk suggests the existence of tissue specific src regulatory pathways that function in activated lymphocytes . . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Lsk is a protein tyrosine kinase with homology to the COOH terminal Src kinase ( Csk ) . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Functional studies indicated that MATK can phosphorylate the carboxyl terminal conserved tyrosine of the Src protein . ^^^ These results support the notion that MATK acts as a regulator of p60c src in megakaryocytic cells and participates in the pathways regulating growth of cells of this lineage . . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Sequence comparisons also indicate that matk contains src homology region 2 and 3 domains but lacks the NH 2 terminal myristylation signal , the negative regulatory tyrosine ( Tyr 527 ) , and the autophosphorylation site ( Tyr 416 ) corresponding to those found in src . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| To address whether Src activity is essential for Neu mediated tumorigenesis , we used a physiologic inhibitor of Src kinase activity , the Csk homologous kinase ( CHK ) , expressed as a mammary tissue specific transgene . ^^^ Our data , using a physiologic inhibitor of Src activity ( CHK ) , showed that blocking of Neu induced Src activity without altering Src expression levels had no significant effects on Neu mediated mammary tumorigenesis in vivo . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| The amino acid sequence of Ctk was found to possess 53 % identity with mouse Csk , shared all the predicted structural features of Csk , and was capable of phosphorylating the carboxyl terminal conserved tyrosine of Src family members . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| Csk type protein tyrosine kinase ( Ctk ) is a protein tyrosine kinase with structural and functional similarities to C terminal Src kinase ( Csk ) . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| These results suggest that Ctk is involved in the regulation of neural function and differentiation of male germ cells through interactions with member ( s ) of the Src family kinases . . ^^^ |
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| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P42679 and P12931 |
Pubmed |
SVM Score :0.0 |
| NA |
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