FIG. 1.

Tyrosine phosphorylation of cellular proteins in KS cells after HIV Tat stimulation. Serum-starved KS cells were stimulated with either Tat at 100 ng/ml or polymixin at 100 ng/ml (A) or Tat at 10 ng/ml or 100 ng/ml (B) for the indicated times. Total-cell lysates (100 μg) obtained after cell lysis were fractionated on 10% polyacrylamide gels and subjected to Western blot (WB) analysis with the antiphosphotyrosine antibody 4G10. The arrows indicate the protein bands which show increased tyrosine phosphorylation after Tat treatment. MW, molecular weight in thousands. P-TYR, phosphotyrosine.