Fig. 4

PinX1 is critical in loading NPM to hTERT during early-S Phase. HeLa cells were transfected with respective plasmids for 24 h and synchronized at G1/S boundary by 2 mM hydroxyurea and were fixed at indicated time points. Immunofluorescence analysis showing localization of a GFP-tagged wildtype NPM and PinX1; b GFP-tagged NPM aa117-294 and PinX1; c GFP-tagged NPM E61A + E63A + E56A mutant and PinX1; d pEGFP-C1 vector and PinX1; e Synchronized and unsynchronized non-transfection controls, at indicated stages of cell cycle after release from hydroxyurea block with GFP-tagged signals (green) and anti-PinX1 (red). DAPI (blue) shows nucleus staining. The white arrows indicate co-localization between GFP-tagged proteins and PinX1 where appropriate