The predicted NLS of PABP2 is not an NLS. A)

<p>Fluorescent microscopy images of cells expressing PABP1-eYFP/PABP2-mChFP either untreated or treated with sinefungin (2 µg/ml), heat shock (41°C) or both sinefungin and heat shock for two hours. <b>B)</b> Alignment of TbPABP1, TbPABP2 and ScPAB1p (region between RRM 3 and 4). The predicted NLS of TbPABP2 is highlighted, as well as the NLS of the yeast protein PAB1p <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054004#pone.0054004-Brune1" target="_blank">[74]</a>. <b>C and D)</b> The predicted NLS of <i>T. brucei</i> PABP2 (RLRRER) was exchanged with the equivalent region from PABP1 (ALRQKY) (<b>C</b>) and vice versa (<b>D</b>). Both mutant proteins had cytoplasmic localization identical to the wild type proteins (not shown). Fluorescent microscopy images of untreated cells as well as cells treated with sinefungin, heat shock or both are shown.