Figure 3.

The APVA mutation abrogates the CD3ϵ/Nck-SH3.1 interaction but does not affect Zap70 and ERK phosphorylation in Jurkat cells. A, SPR confirmed the interaction between Nck-SH3.1 and WT CD3ϵ peptide RGQNKERPPPVPNPDY. APVA mutant CD3ϵ peptide RGQNKERPAPVANPDY (squares) binds ∼10-fold less strongly to Nck-SH3.1 than the WT. B and C, WT or APVA mutant Jurkat cells were either left untreated or treated with H₂O₂ or PMA/ionomycin or were stimulated for 5 min with plate-coated anti-CD3 (OKT3). Zap70 (B) and ERK (C) phosphorylation were then measured by flow cytometry. Error bars, S.D.