To investigate additional functions of the T cell adaptor, Src homology 2 (SH2) domain-containing leukocyte protein of 76 kD (SLP-76), we performed a yeast two-hybrid assay using the N-terminal region of SLP-76 fused with the kinase domain of Syk. By screening a human leukemia cDNA library, we identified the p85 subunit of phosphoinositide 3-kinase (PI3K) as one of the interacting molecules. Unlike the SH2 domain of Vav or Nck, tyrosine phosphorylation of SLP-76 at position 113 or 128 was sufficient for it to associate with the N-terminal SH2 of p85. Collectively, these data suggest that SLP-76 may play a role in PI3K signaling pathways.
Bibliographical noteFunding Information:
We thank Drs. Alex Toker, André Veillette, and Gary Koretzky for providing valuable reagents. This study was supported by a grant from the Korea Health 21 R&D project, Ministry of Health and Welfare, Republic of Korea (00-PJ1-PG3-21200-0045), and another from the Korea Science and Engineering Foundation through the Center for Cell Signaling Research at Ewha Womans University. E.K.S., J.Y.L., and Y.J.H. were supported in part by the Brain Korea 21 Program of the Korea Ministry of Education.
- Ab, antibody
- IB, immunoblotting
- IP, immunoprecipitation
- PI3K, phosphoinositide 3-kinase
- PTK, protein tyrosine kinase
- SH2, Src homology 2
- SLP-76, Src homology 2 domain-containing leukocyte phosphoprotein of 76 kD
- TCR, T cell receptor
- WT, wild-type