TbSKP1 promotes progression through the G1/S transition of the T. brucei cell cycle.

<p>(A) Growth curves of PCF TbSKP1-RNAi (left panel) and BSF TbSKP1-RNAi (right panel) parasites after tetracycline-induced RNAi. PCF or BSF parasites transfected with the pZJM-TbSKP1-RNAi construct were cultured in the absence (-TET) or presence (+TET) of tetracycline (1μg/ml). Insets in the respective growth curves show northern blot (PCF) or RT-qPCR (BSF) experiments demonstrating the RNAi-mediated downregulation of TbSKP1 mRNA. Error bars represent the ± SEM of 3 biological replicates. **: <i>p≤ 0</i>.<i>001</i>. (B) Flow cytometry analysis of PCF (left panels) and BSF (right panels) TbSKP1-RNAi parasites. The x-axis shows fluorescence intensity in the FL2-A channel. Bottom panel of each analysis shows the percentage of cells in each phase of the cell cycle as determined using Flowjo software. (C) DAPI analysis of nuclei and kinetoplast in PCF (left panel) and BSF (right panel) cells at different time points. These results are representative of at least three experiments. At least 100 cells were counted for each time point. (D) Images of BSF DAPI-stained cells viewed by phase-contrast and fluorescence microscopy. <i>N</i>: nucleus, <i>K</i>: kinetoplast.</p>