FIGURE 6.

HDAC1 or HDAC2 complexes are catalytically active during mitosis. A, HDAC1 or HDAC2 complexes were isolated by immunoprecipitation with anti-HDAC1 or anti-HDAC2 antibodies from cycling (cyc) and nocodazole-treated HeLa cells (mit). HDAC activity in the immunoprecipitated fractions was measured by fluorometric activity assay kit. The activity of the HDAC1/2 complexes represents the average of three independent experiments and is relative to the activity from a non-related IgG control in cycling cells (without TSA treatment, which is set to 1 in all experiments) in arbitrary units. Error bars, S.D. B, representative immunoblot analysis (IB) from three independent experiments of HDAC1 and HDAC2 complexes in cycling (Noc−) and mitotic HeLa cells (Noc+) for corresponding HDAC activity assay shows that HDAC1 and HDAC2 did not interact with each other during mitosis. HDAC2*, phosphorylated form of HDAC2.