A peptide library approach identifies a specific inhibitor for the ZAP-70 protein tyrosine kinase.
We utilized a novel peptide library approach to identify specific inhibitors of ZAP-70, a protein Tyr kinase involved in T cell activation. By screening more than 6 billion peptides oriented by a common Tyr residue for their ability to bind to ZAP-70, we determined a consensus optimal peptide. A Phe-for-Tyr substituted version of the peptide inhibited ZAP-70 protein Tyr kinase activity by competing with protein substrates (K(I) of 2 microM). The related protein Tyr kinases, Lck and Syk, were not significantly inhibited by the peptide. When introduced into intact T cells, the peptide blocked signaling downstream of ZAP-70, including ZAP-70-dependent gene induction, without affecting upstream Tyr phosphorylation. Thus, screening Tyr-oriented peptide libraries can identify selective peptide inhibitors of protein Tyr kinases.
Nishikawa
K
K
Division of Signal Transduction, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02115, USA.
Sawasdikosol
S
S
Fruman
D A
DA
Lai
J
J
Songyang
Z
Z
Burakoff
S J
SJ
Yaffe
M B
MB
Cantley
L C
LC
D000595:Amino Acid Sequence; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D017930:Genes, Reporter; D006801:Humans; D007376:Interleukin-2 / Q000235:genetics; D007527:Isoenzymes / Q000378:metabolism; D019169:Jurkat Cells; D007700:Kinetics; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D019151:Peptide Library; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D051966:Phospholipase C gamma; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*; D013601:T-Lymphocytes / Q000201:enzymology / Q000276:immunology; D014162:Transfection; D010738:Type C Phospholipases / Q000378:metabolism; D051746:ZAP-70 Protein-Tyrosine Kinase
D004791:Enzyme Inhibitors; D007376:Interleukin-2; D007527:Isoenzymes; D019151:Peptide Library; D010455:Peptides; D011505:Protein-Tyrosine Kinases; D051746:ZAP-70 Protein-Tyrosine Kinase; C497261:ZAP70 protein, human; D010738:Type C Phospholipases; D051966:Phospholipase C gamma