Visualization of Chromosomes and Nuclear Envelope in Living Cells for Molecular Dynamics Studies

All Fluorescence, All the Time Translocation of proteins in living cells is frequently tracked using green fluorescent protein (GFP) fusion proteins and time-lapse video microscopy. Visualization of nonfluorescence-labeled reference structures in the cell can be accomplished using phase contrast or differential interference contrast microscopy. Simultaneous time-lapse visualization of fluorescent and nonfluorescent targets, however, can require sophisticated and costly instrumentation. Fukada et al. (p. 552) describe an all fluorescence system for visualizing protein translocation during mitosis in living cells that neatly circumvents this problem. The authors track the movement of enhanced GFP (EGFP)-labeled aurora-A in cells stably expressing ECFP-labeled histone H3 and DsRed-labeled importin 1α. In this system, H3 and importin 1α serve as markers of chromosome and nuclear membrane localization, respectively. The authors show that, using appropriate filter sets, they are able to distinguish the fluoresc...