FIG. 7.

INO80 does not have an H4 N-terminal histone tail requirement for binding or ATP hydrolysis. (A) The affinity of INO80 for nucleosomes with and without particular histone tails were measured by gel shift analysis. Increasing amounts of INO80 (5, 10, 20, and 40 nM) were bound with 33 nM nucleosomes for 30 min at 30°C and analyzed on a 4% native PAGE gel in 1× TE. (B) The rate of ATP hydrolysis was measured for the same nucleosome substrates as described in panel A, with INO80 (6.7 nM) prebound to nucleosomes (33 nM) for 15 min at 30°C. ATP was added to a final concentration of 80 μM and incubated for the indicated times. Reactions were stopped with SDS and EDTA as described in Materials and Methods and analyzed by thin-layer chromatography.