Figure 5From: Polycomblike protein PHF1b: a transcriptional sensor for GABA receptor activity PHF1b protein nuclear localization in rat neocortical neurons. Primary rat neocortical neurons isolated from E18 brain and maintained one week in vitro were transfected with GFP-PHF1b fusion plasmids (CMV-GFP-PHF1b, CMV-GFP-PHF1b-Δ5, CMV-GFP-PHF1b-Δ3, see Figure 3) and examined 48 hours after transfection by confocal microscopy for nuclear localization relative to DsRed-Nuclear marker (CMV-DsRed-Nuclear), a red fluorescent protein that localizes to the nucleus. Control transfection of CMV-GFP (A, C) and CMV-DsRed-Monomer (B, C) construct expression is throughout cortical cells and expression is not restricted to the nucleus (C). Both GFP-PHF1b (D, F) and GFP-PHF1b-Δ5 (G, I) fusion construct expression coincides with DsRed-Nuclear (E, F and H, I) indicating that both the PHF1b and the PHF1b-Δ5 protein contain a nuclear localization signal. In contrast, the GFP-PHF1b-Δ3 (J, L) fusion construct expression is not restricted to the nucleus (DsRed-Nuclear, K, L) suggesting that the nuclear localization signal of PHF1b is not localized at the N-terminus of the PHF1b protein. Scale bar is 10 μm.Back to article page