Figure 2. Charon encodes a PARP-1-dependent chromatin-associated protein.

A–C. Charon protein is a nuclear protein. In wild-type Drosophila tissues (A), it bound to ~ 400 sites in chromatin, presenting in soluble nucleoplasm (arrow) and accumulating in cytoplasmic perinuclear bodies (arrowheads). It accumulates in nucleoplasmic bodies in parg^27.1 mutants (B) and in soluble nucleoplasm in parp-1^C03265 mutants (C). D. Charon protein interacts with PARP-1 protein in chromatin. Co-immunoprecipitation experiments: nuclei were purified from animals expressing CG5118-GFP and PARP-1-DsRed proteins; samples were treated with MNase (+) to digest chromatin to mononucleosomal state; untreated nuclei were used as a control (−); chromatin was extracted, and protein complexes were precipitated using anti GFP antibody or IgG; samples were subjected to Western blot analysis using anti-DsRed, anti hnRNP A1 and anti-histone H4 antibodies.