A conserved ARTD10 region encompassing amino acids 435–528 mediates nuclear uptake. A. The indicated CFP-YFP fusion proteins were expressed transiently in COS7 cells in the presence or absence of LMB. Their subcellular distribution was determined by confocal microscopy. B. Above the schematic structural organization of ARTD10, evolutionary conserved regions of the protein are denoted with a black bar. The conserved region in the central part of ARTD10 encompassing amino acids 435–528 is shown for zebra fish, stickleback, human, mouse, medaka, and two pufferfish (from top to bottom). C. GFP-β-Gal, GFP-β-Gal-ARTD10(435–555), and GFP-β-Gal-ARTD10(455–555) were expressed transiently in COS7 cells and the subcellular distribution of the different fusion proteins analyzed by confocal microscopy. Below the micrographs intensity profiles are shown, which were measured from the areas indicated by the red arrow. Mean intensities were determined in the cytoplasm and in the nucleus as indicted in the profiles. These intensities were used to assess the ratio of cytoplasmic/nuclear staining as summarized in panel D. D. Summary of the ratio of mean cytoplasmic vs. mean nuclear florescence of the indicated fusion proteins (examples of single cells are shown in panel C).