| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.89366838 |
| By contrast , CD 19 was markedly tyrosine phosphorylated and was associated with lyn and PI 3 K . 0.89366838^^^ CD 38 ligation in human B cell progenitors triggers tyrosine phosphorylation of CD 19 and association of CD 19 with lyn and phosphatidylinositol 3 kinase . 0.50176693^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :1.0184739 |
| In wild type B cells , CD 19 was constitutively complexed with Vav , Lyn , and other Src family PTKs , with CD 19 phosphorylation and its associations with Lyn and Vav increased after BCR ligation . 1.0184739^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.66870353 |
| Herein , we demonstrate a novel molecular mechanism where interactions between CD 19 and Lyn amplify basal and antigen receptor induced Src family kinase activation . 0.66870353^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :1.0203449 |
| To identify the outcome of interactions between CD 19 and Src family PTKs in vivo , B cell function was examined in mice deficient for CD 19 and Lyn ( CD19 / Lyn ( / ) ) . 1.0203449^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.568849 |
| CD 19 formed a complex with Lyn and Vav following RP 105 ligation , and CD 19 expression was required for optimal Lyn activation and Vav phosphorylation . 0.568849^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| CD 19 is coupled , via protein tyrosine kinases ( PTKs ) , to PLC and phosphatidylinositol 3 ' kinase ( PI 3 ' kinase ) , and it interacts with the Src type nonreceptor PTK lyn . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| Membrane associated CD 19 LYN complex is an endogenous p 53 independent and Bc 1 2 independent regulator of apoptosis in human B lineage lymphoma cells . ^^^ CD 19 receptor is expressed at high levels on human B lineage lymphoid cells and is physically associated with the Src protooncogene family protein tyrosine kinase Lyn . ^^^ Recent studies indicate that the membrane associated CD 19 Lyn receptor enzyme complex plays a pivotal role for survival and clonogenicity of immature B cell precursors from acute lymphoblastic leukemia patients , but its significance for mature B lineage lymphoid cells ( e . g . , B lineage lymphoma cells ) is unknown . ^^^ CD 19 associated Lyn kinase can be selectively targeted and inhibited with B 43 Gen , a CD 19 receptor specific immunoconjugate containing the naturally occurring protein tyrosine kinase inhibitor genistein ( Gen ) . ^^^ We now present experimental evidence that targeting the membrane associated CD 19 Lyn complex in vitro with B 43 Gen triggers rapid apoptotic cell death in highly radiation resistant p 53 Bax Ramos BT B lineage lymphoma cells expressing high levels of Bcl 2 protein without affecting the Bcl 2 expression level . ^^^ |
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| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| Several second messenger proteins have been shown to immunoprecipitate with CD 19 , including p 59 Fyn ( Fyn ) , p 59 Lyn ( Lyn ) and phosphatidylinositol 3 kinase ( PI 3 kinase ) . ^^^ However , the reported consensus binding sequence for the Fyn and Lyn SH 2 domains ( YPO 4 10 10 I / L ) is not found in CD 19 . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| Further , protein tyrosine kinase lyn , which is activated by the antigen receptor , can be readily co immunoprecipitated with CD 19 suggesting this is the enzyme responsible for the antigen receptor mediated tyrosine phosphorylation of CD19 . . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| We here show that CD 19 is tightly linked to the non receptor src kinase Lyn and that the CD 19 glycoprotein itself serves as a substrate for a yet undefined serine / threonine kinase present within the complex . ^^^ We hypothesize that in this process , approximation to the BCR allows CD 19 associated Lyn kinase to phosphorylate potential substrates within the antigen receptor complex , thereby effecting its coupling to the intracellular compartment . . ^^^ |
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| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| Furthermore , tyrosine phosphorylation of CD 19 , a known substrate of lyn , was inducible in anti IgM stimulated BKS 2 cells but severely reduced in 1 . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| Using a CD 19 reconstituted myeloma model and CD 19 gene ablated animals we found that BCR mediated Btk activation and phosphorylation are dependent on the expression of CD 19 , while BCR mediated activation of Lyn and Syk is not . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| This process has been proposed to be mediated by an interaction between the Src family kinase LYN and the p 85 subunit of PI3K and / or through p 85 membrane recruitment mediated by CBL and / or CD 19 . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| Loss of Lyn , PTEN ( phosphatase and tensin homolog ) , or SH 2 containing inositol phosphatase suppressed the Btk ( lo ) phenotype in vitro but not in vivo , whereas CD 19 and the p85alpha form of phosphoinositide 3 kinase behaved as Btk ( lo ) enhancers in vivo but not in vitro . ^^^ |
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| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| The SH 2 domain containing tyrosine phosphatase 1 down regulates activation of Lyn and Lyn induced tyrosine phosphorylation of the CD 19 receptor in B cells . ^^^ As CD 19 tyrosine phosphorylation is modulated by the Lyn protein tyrosine kinase , Lyn activity was evaluated in wild type and motheaten B cells . ^^^ The results revealed both Lyn as well as CD 19 associated Lyn kinase activity to be constitutively and inducibly increased in SHP 1 deficient compared with wild type B cells . ^^^ These findings , together with cyanogen bromide cleavage data revealing that SHP 1 dephosphorylates the Lyn autophosphorylation site , identify Lyn deactivation / dephosphorylation as a likely mechanism whereby SHP 1 exerts its influence on CD 19 tyrosine phosphorylation and , by extension , its inhibitory effect on B cell antigen receptor signaling . . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| CD 19 amplification of Lyn activity leads to processive phosphorylation of CD 19 and downstream substrates including CD 22 . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| CD 19 amplification of B lymphocyte Ca2+ responses : a role for Lyn sequestration in extinguishing negative regulation . ^^^ Although simultaneous CD 19 and BCR engagement significantly enhanced CD19 / Lyn complex formation and [ Ca ( 2+ ) ] ( 1 ) responses , downstream tyrosine phosphorylation of CD 22 and multiple other cellular proteins was inhibited , as was SHP 1 recruitment to phosphorylated CD 22 . ^^^ Because CD 19 and Lyn expression are genetically titrated in B cells , CD 19 engagement may augment BCR induced [ Ca ( 2+ ) ] ( 1 ) responses by sequestering the available pool of functional Lyn away from downstream negative regulatory proteins such as CD 22 . ^^^ Consistent with this , simultaneous CD 19 engagement did not further enhance the BCR induced [ Ca ( 2+ ) ] ( 1 ) responses of Lyn or CD 22 deficient B cells . ^^^ Thus , CD 19 recruitment of Lyn may preferentially activate selective signaling pathways downstream of the CD19 / Lyn complex to the exclusion of other downstream regulatory and effector pathways . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| CD 19 deficiency increased the affinity threshold of TI 2 responses , whereas Lyn deficiency enhanced clonal expansion but abrogated B cell terminal differentiation . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| CD 19 mediated [ Ca ( 2+ ) ] ( 1 ) responses , Vav phosphorylation , and Lyn kinase activity were similarly enhanced . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| In both B 1 and B 2 cells BCR cross linking induced a modest increase of CD 19 associated Lyn , a Src family protein tyrosine kinase ( PTK ) thought to be important for CD 19 phosphorylation . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| The activation and subsequent regulatory roles of Lyn and CD 19 after B cell receptor ligation are independent . ^^^ The cell surface glycoprotein CD 19 and the Src related protein tyrosine kinase Lyn are key mediators of , respectively , positive and negative signaling in B cells . ^^^ Despite the apparent opposition of their regulatory functions , a recent model of the biochemical events after B cell receptor ( BCR ) ligation intimately links the activation of Lyn and CD 19 . ^^^ We examined the biochemical consequences of BCR ligation in mouse B cells lacking either Lyn or CD 19 for evidence of interaction or codependence . ^^^ In contrast to published results , we found CD 19 phosphorylation after BCR ligation to be unaffected by the absence of Lyn , yet dependent on Src family protein tyrosine kinases as it was inhibited fully by PP 2 , an Src family specific inhibitor . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| CD 19 immunoprecipitates contain a complex of cytoplasmic proteins , including Lyn , Vav , phospholipase Cgamma 2 ( PLCgamma 2 ) , Grb 2 , and the p 85 subunit of phosphatidylinositol 3 kinase . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| SA C3dg enhancement of BCR induced [ Ca2+ ] 1 responses required CD 21 and CD 19 expression and resulted in significantly enhanced CD 19 and Lyn phosphorylation , with enhanced Lyn / CD19 associations . ^^^ By contrast , CD19 / CD21 ligation using higher concentrations of SA C3dg significantly inhibited BCR induced [ Ca2+ ] 1 responses and inhibited CD 19 , Lyn , CD 22 , and Syk phosphorylation . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| In this review , we discuss the potential role of molecules involved in altered B cell longevity , especially molecules involved in apoptosis ( bcl 2 , bcl 10 , mutations in the Fas / Fas L pathway ) , as well as molecules that might alter activation thresholds of B cells ( CD 19 , CD 21 , CD 22 , lyn , SHP , SHIP 1 ) in the development of autoimmunity . ^^^ |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: P15391 and P07948 |
Pubmed |
SVM Score :0.0 |
| NA |
|