May confer resistance to the antitumor agent cisplatin. Binds to DNA and RNA (By similarity). Homodimer. After treatment with proteasomal inhibitors and mild heat-shock stress is relocalized to the nucleolus as dot-like or irregular subnuclear structures. Colocalized with nuclear promyelocytic leukemia (PML) and Cajal bodies (CB); this association with nuclear bodies is enhanced in response to proteotoxic stress. Relocalized in nucleolar caps during transcriptional arrest (By similarity). C-terminal half contains cytoplasmic retention domains as well as determinants involved in its stress-induced nucleolar accumulation.