A, NK clones infected with WR or Dyn2 recombinant vaccinia virus were stimulated for the indicated times with anti-FcR and then lysed. PLCγ2, Vav, and SLP-76 were then immunoprecipitated from the lysates followed by SDS-PAGE and immunoblot for p-tyr or the indicated proteins. B, NK clones electroporaed with negative control siRNA or Dyn2 suppressing siRNA were stimulated for the indicated times with anti-FcR and then lysed. PLCγ2, Vav, and SLP-76 were then immunoprecipitated and analyzed as in A. The experiments shown are representative of 3 independent experiments. Lysates were equalized for protein expression and blotted for Dyn2 to verify suppression of the protein (inset, B). C, NK clones were electroporated with control or Dyn2 siRNA. Forty-eight hours post electroporation, calcium mobilization in response to anti-FcR/goat anti-mouse was measured using Indo-1 staining and flow cytometry. Data shown are representative of 2 independent experiments.