Back to Search
Start Over
Molecular cloning of SKAP55, a novel protein that associates with the protein tyrosine kinase p59fyn in human T-lymphocytes
- Source :
- The Journal of biological chemistry. 272(26)
- Publication Year :
- 1997
-
Abstract
- In human T-lymphocytes the Src family protein tyrosine kinase p59fyn associates with three phosphoproteins of 43, 55, and 85 kDa (pp43, pp55, and pp85). Employing a GST-Fyn-Src homology 2 (SH2) domain fusion protein pp55 was purified from lysates of Jurkat T-cells. Molecular cloning of the pp55 cDNA reveals that the pp55 gene codes for a so far nondescribed polypeptide of 359 amino acids that comprises a pleckstrin homology domain, a C-terminal SH3 domain, as well as several potential tyrosine phosphorylation sites, among which one fulfills the criteria to bind Src-like SH2 domains with high affinity. Consistent with this observation, pp55 selectively binds to isolated SH2 domains of Lck, Lyn, Src, and Fyn but not to the SH2 domains of ZAP70, Syk, Shc, SLP-76, Grb2, phosphatidylinositol 3-kinase, and c-abl in vitro. Based on these properties the protein was termed SKAP55 ( s rc kinase-associated phosphoprotein of55 kDa). Northern blot analysis shows that SKAP55 mRNA is preferentially expressed in lymphatic tissues. SKAP55 is detected in resting human T-lymphocytes as a constitutively tyrosine phosphorylated protein that selectively interacts with p59fyn. These data suggest that SKAP55 represents a novel adaptor protein likely involved in Fyn-mediated signaling in human T-lymphocytes.
- Subjects :
- T-Lymphocytes
Molecular Sequence Data
Protein tyrosine phosphatase
SH2 domain
Proto-Oncogene Proteins c-fyn
environment and public health
Biochemistry
Receptor tyrosine kinase
SH3 domain
src Homology Domains
chemistry.chemical_compound
Proto-Oncogene Proteins
Humans
Amino Acid Sequence
Cloning, Molecular
Molecular Biology
biology
Base Sequence
Tyrosine phosphorylation
Cell Biology
Phosphoproteins
Pleckstrin homology domain
Molecular Weight
src-Family Kinases
chemistry
biology.protein
GRB2
Proto-oncogene tyrosine-protein kinase Src
Subjects
Details
- ISSN :
- 00219258
- Volume :
- 272
- Issue :
- 26
- Database :
- OpenAIRE
- Journal :
- The Journal of biological chemistry
- Accession number :
- edsair.doi.dedup.....082fac46197184ac727c17703416c188