Expression and utilization of LAB in RNKD2.38 and LAT^−/− NK cells. (A) Equal amounts of protein from lysates of T cell–depleted ALAK cells from the indicated strains were directly immunoblotted with anti-Syk or anti-ZAP70 as indicated (bottom 2 panels). The same lysates were also immunoprecipitated, then immunoblotted with anti-LAT or anti-LAB as indicated (top 2 panels). (B) RNKD2.38 were stimulated with anti-Ly49D (4E5) for the indicated time and lysates were incubated with GST-Grb2. Bound proteins were resolved by SDS-PAGE and immunoblotted with anti–phospho-LAT/LAB. (C) LAT^−/− ALAK cells were stimulated and incubated with GST-Grb2 as in B, and immunoblotted with anti-LAB. Results shown are representative of 2 or more independent experiments.