Subnuclear localization of PCNA-interacting proteins during S phase in Drosophila cells. (A) Plasmid constructs used to evaluate the association of mammalian replication proteins with RF in S2 cells. Mammalian cells expressing: NMT-GFP (B), GFP-HsLig (F). Drosophila cells expressing: NMT-GFP (C), Dnmt1 (D), GFP-HsLig (E), MTPBD-GFP (G-top panel) and HsLigPBD-GFP (G-bottom panel). RF were detected by BrdU incorporation and immunostaining with anti-BrdU. In (C) arrows in bottom panel show aggregation of NMT-GFP in large structures that are excluded from BrdU incorporation sites. In (D) top panel represents pattern observed in 80–90% of cells and bottom panel represents pattern observed in 10% of cells. Overlays show merge of green and red images. Scale bar = 2 μm.