Fig. 3. GFP-IMP1 localization. (A) Time-lapse microscopy of NIH 3T3 cells that stably express GFP-IMP1. Cells with GFP-IMP1 undergoing localization are marked by arrows. (B) Velocity of moving GFP-IMP1 granules. Particles were followed by time-lapse microscopy at 20 second intervals. The velocities of 100 individual particles were calculated by measuring the distance between the particles in two succesive frames. (C) Fluorescence recovery after photobleaching. A cellular extension was bleached, and the transport of GFP-IMP1 into the bleached area was followed by time-lapse microscopy at 20 second intervals in the absence and presence of sodium azide and 2-deoxyglucose. A similar experiment with GFP-ß-galactosidase is included as a control.