SKAP‐HOM, a novel adaptor protein homologous to the FYN‐associated protein SKAP55

FEBS Letters

Eckerskorn, Christoph²  Verhagen, Anne M.¹  Marie-Cardine, Anne¹  Schraven, Burkhart¹ 

[1] Ruprecht-Karls University of Heidelberg, Institute for Immunology, Im Neuenheimer Feld 305, 69120 Heidelberg, Germany;Max-Planck Institute for Biochemistry, 82152 Martinsried, Germany

关键词: T lymphocyte;    Signal transduction;    Protein tyrosine kinase;    EST;    expressed sequence tag;    GST;    glutathione S-transferase;    SKAP55;    src kinase associated phosphoprotein of 55 kDa;    SLAP-130;    SLP76 associated phosphoprotein of 130 kDa;    PH;    pleckstrin homology;    SH2 and 3;    src homology 2 and 3;    PTK;    protein tyrosine kinase;    IEF;    isoelectric focusing;   

DOI  :  10.1016/S0014-5793(98)01040-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A recombinant GST-Fyn-SH2 domain was used to purify proteins from lysates of pervanadate treated EL4 cells. N-terminal sequencing and molecular cloning of one of the purified polypeptides resulted in the identification of a novel adaptor protein that shares strong structural homology to the recently cloned Fyn-associated adaptor protein SKAP55. This protein was termed SKAP-HOM (55 ologue). Despite their striking homology, SKAP55 and SKAP-HOM have distinct characteristics. Thus, unlike SKAP55, which is exclusively expressed in T lymphocytes, SKAP-HOM expression is ubiquitous. Furthermore, while SKAP55 is constitutively tyrosine phosphorylated in resting human T cells, SKAP-HOM is expressed as a non-phosphorylated protein in the absence of external stimulus but becomes phosphorylated following T cell activation. In addition, SKAP-HOM does not associate with p59^fyn in T cells although it represents a specific substrate for the kinase in COS cells. Finally, we demonstrate that, as previously shown for SKAP55, SKAP-HOM interacts with the recently identified polypeptide SLAP-130.

【 授权许可】

Unknown