Figure 2.

Gro interacts with core histones. (A) Coomasie blue stained gel of E.coli produced and purified GST–histone tail fusion proteins. Approximately equal amounts of each of the different fusion proteins were used for the interaction assay. (B) Autoradiogram of an SDS–PAGE gel showing ³⁵S-Gro or ³⁵S-Tup1 retained by affinity beads containing GST or fusion proteins containing GST and various histone N-terminal tails. (C) Calf thymus histones (CTH) and Drosophila core histones (DH) were resolved in a 20% SDS–polyacrylamide gel, transferred to nitrocellulose membranes and stained with Ponceau-S or incubated with nuclear extract from Sf9 cells expressing FLAG-Gro. The Gro-interacting histones were identified by subsequent incubation with anti-FLAG antibodies. (D) GST-pulldown with bacterially made GST–H3 tail and GST–H4 tail fusion proteins and purified FLAG-Gro from baculovirus infected Sf9 cells. Bound Gro was detected by immunoblot analysis of the retained fraction.