Figure 4.

(A) HDAC3 is involved in N-CoR/Pit-1-mediated repression. A reporter plasmid containing a Pit-1 response element was microinjected into 293 cells in the presence of control IgG, anti-N-CoR, or anti-HDAC3 IgG. The results were quantified as the percentage of injected cells (by rhodamine staining) that also turned blue [by 5-bromo-4-chloro-3-indolyl β-d-galactoside (X-Gal) staining] and shown here as the averages ± SD of two experiments performed in triplicate. (B and C) N-CoR HDAC3-interacting domain enhances deacetylase activity by HDAC3. Recombinant Flag-HDACs and Gal4-N-CoR fusion proteins were expressed in Sf9 cells, immunoprecipitated with an anti-Flag Ab. Precipitates were divided into three equal aliquots and used for deacetylase assays (B), analysis by Western blot by using the anti-Flag Ab (C Left), and analysis by Western blot by using an anti-Gal4 Ab (C Right). Deacetylase results are the averages ± SD from four separate experiments.