Fig. 2. SUUR interacts with HP1 in vitro. The ability of the full-length SUUR and its central portion (AA 371-578) to recruit HP1 from Drosophila embryo nuclear extracts was tested by GST pull-down assays. GST alone, GST-SUUR (AA 1-962) and GST-SUUR (AA 371-578) were produced in bacteria and immobilized on glutathione-Sepharose beads. The beads were then incubated with nuclear extracts of wild-type Drosophila embryos. Bound proteins were washed, resolved by SDS-PAGE, and transferred to nitrocellulose. The blot was probed with antibodies against HP1. The amount in the input column is 5% of the amount applied to beads. SUUR constructs employed in the experiment are schematically depicted below the blot; the homology region to the SNF2 domain is in yellow, the homology region to the bromodomain is in brown, the negatively charged amino acid clusters are in blue, the positively charged amino acid clusters are in red, the NLSs are in grey.