Figure 4.

Mapping of the TRX SET histone-binding domain. SET domain deletion fragments were tested for their ability to bind core histones in GST pull-down experiments. Protein complexes were resolved by 15% SDS-PAGE and analyzed by Western immunoblotting using anti-Drosophila histone antibodies The residues present in the SET deletion fragments (SDF1–13) are indicated. Two highly conserved blocks with homology to plant methylases, a C-terminal cysteine-rich region, and the position of the trx^Z11 glycine to serine (G₃₆₀₁>S) mutation are schematically depicted. The identified minimal histone-binding domain and the N-terminal and C-terminal domains, which play a critical role in histone binding, are shown.