Bruton's tyrosine kinase (Btk) associates with protein kinase C μ

FEBS Letters

Pfizenmaier, Klaus²  Hausser, Angelika²  Link, Gisela²  Storz, Peter²  Truckenmüller, Lars²  Johannes, Franz-Josef²  Kawakami, Toshiaki¹ 

[1] Division of Allergy, La Jolla Institute for Allergy and Immunology, 10335 Science Center Drive, San Diego, CA 92121, USA;Institute of Cell Biology and Immunology, University of Stuttgart, Allmandring 31, 70569 Stuttgart, Germany

关键词: PKC;    protein kinase C;    GST;    glutathione S-transferase;    Pdbu;    phorbol 12;    13-dibutyrate;    Btk;    Bruton's tyrosine kinase;    SDS-PAGE;    sodium dodecylsulfate-polyacrylamide gel electrophoresis;    xid;    X-chromosome linked immunodeficiency;    JNK;    c-Jun N-terminal kinase;   

DOI  :  10.1016/S0014-5793(99)01424-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Bruton's tyrosine kinase (Btk) is considered an essential signal transducer in B-cells. Mutational defects are associated with a severe immunodeficiency syndrome, X-chromosome linked agammaglobulinemia (XLA). Here we show by coimmunoprecipitation that a member of the protein kinase C (PKC) family, PKCμ, is constitutively associated with Btk. Neither antigen receptor (Ig) crosslinking nor stimulation of B-cells with phorbol ester or H₂O₂ affected Btk/PKCμ interaction. GST precipitation analysis revealed association of the Btk pleckstrin/Tec homology domain with PKCμ. Transient overexpression of PKCμ deletion mutants as well as expression of selected PKCμ domains in 293T cells revealed that both the kinase domain and the regulatory C1 region are independently capable of binding to the Btk PH-TH domain. These data show the existence of a PKCμ/Btk complex in vivo and identify two PKCμ domains that participate in Btk interaction.

【 授权许可】

Unknown