FIG. 4.

Acetylation of GATA-1 in vivo. (A) Lysates from MEL cells pulse-labeled with 1 mCi of [³H]acetate per ml in the presence of 50 nM Trichostatin A were immunoprecipitated with anti-GATA-1 antibodies or isotype-matched irrelevant antibodies (ctr). Immunoprecipitated samples were resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and enhanced by fluorgraphy. (B) (Top) Whole-cell lysates from transfected COS cells were immunoprecipitated (I.P.) with anti-AK antibodies and analyzed for the presence of wild-type or mutant GATA-1 by Western blotting. Mutant contructs are as described in Fig. 2. ctr, untransfected COS cells; wt, wild type. (Bottom) Western blotting of unprecipitated lysates confirms the presence of similar amounts of GATA-1 proteins. (C) Whole-cell lysates from transfected NIH 3T3 cells were immunoprecipitated as in panel B.