Ntroller of cell cycle progression [9]. We also find that in MCF10A cells, GABPA plays an important role in controlling the activity of a programme of genes involved in cell cycle control (Fig. 2B; Figs. S3. S4) and it appears to do this by both indirect anddirect mechanisms. In keeping with this finding, depletion of GABPA in MCF10A cells leads to changes in their overall cell cycle distributions (data not shown). In another study, the analysis of the entire GABPA regulome led to the identification of many of the functional categories that also appear in our data as potentially directly regulated by GABPA such as “transcriptional regulators”GABPA and Cell Migration ControlFigure 4. Depletion of direct target genes of GABPA slows 18334597 down MCF10A cell migration. (A) Graph shows the mRNA levels of four GABPA target genes in cells transfected with the respective siRNA species. Values were normalised to control (siGAPDH transfection) and are presented on one chart for clarity. Bars represent average values from three biological repeats with standard deviation. Statistical significance was determined in Student’s paired t-tests (*P,0.001). (B and C) MCF10A cells were transfected with the indicated siRNAs, starved for EGF for 48 hours, stimulated with media containing 20 ng/ml EGF and imaged for 24 hours. (B) Shown are trajectories travelled by cells in the first six hours of live imaging experiments in the presence of the siRNA species indicated above each graph (only three out of the six sets of trajectories are depicted). (C) Box plots show the distributions of lengths of trajectories travelled by MCF10A cells transfected with the indicated siRNA species between t = 1 h and t = 7 h after the addition of EGF (which corresponds to t = 0 to t = 6 h of imaging). Data was obtained in three biological repeats of the experiment, in each case ten cells were manually tracked. The green and pale yellow areas correspond to the second and third quartile of the distribution, respectively. The shaded area represents the distribution of distances covered in control siGAPDH-transfected cells. P-values were obtained in a SmirnovKolomogorov test (*P,0.05 ** P,0.001). doi:10.1371/journal.pone.0049892.gin addition to “cell cycle regulation” [8]. However, by further subpartitioning GABPA targets according to regulatory mode, our study provides further insight and suggests that many of these categories are upregulated by GABPA activity. Indeed, overall the predominant mode of action for GABPA appears to be as a transcriptional activator (Fig. 2A [8]). Conversely, we show that 1407003 GABPA depletion also causes upregulation of gene expression, implying a buy GW0742 repressive role, even in the context of direct target genes. Interestingly, several genes encoding transcriptional repressors (e.g. NCOR2, HDAC5, BCL6, BCOR) are upregulated upon GABPA depletion which might then cause some of the observed decreases in gene expression. In this study we made use of available ChIP-seq data for GABPA to distinguish between likely directly and indirectly regulated targets. While enrichment of GO term categories relating to the cytoskeleton were identified as controlled by GABPA in the entire regulome, these categories were not apparent when direct GABPA targets were analysed, suggesting that the effect of depletion of this factor on cell migration is at least MedChemExpress GSK864 partially secondary. However, importantly, we also uncovered a set ofpotential key regulators of cell migration that are direct targe.Ntroller of cell cycle progression [9]. We also find that in MCF10A cells, GABPA plays an important role in controlling the activity of a programme of genes involved in cell cycle control (Fig. 2B; Figs. S3. S4) and it appears to do this by both indirect anddirect mechanisms. In keeping with this finding, depletion of GABPA in MCF10A cells leads to changes in their overall cell cycle distributions (data not shown). In another study, the analysis of the entire GABPA regulome led to the identification of many of the functional categories that also appear in our data as potentially directly regulated by GABPA such as “transcriptional regulators”GABPA and Cell Migration ControlFigure 4. Depletion of direct target genes of GABPA slows 18334597 down MCF10A cell migration. (A) Graph shows the mRNA levels of four GABPA target genes in cells transfected with the respective siRNA species. Values were normalised to control (siGAPDH transfection) and are presented on one chart for clarity. Bars represent average values from three biological repeats with standard deviation. Statistical significance was determined in Student’s paired t-tests (*P,0.001). (B and C) MCF10A cells were transfected with the indicated siRNAs, starved for EGF for 48 hours, stimulated with media containing 20 ng/ml EGF and imaged for 24 hours. (B) Shown are trajectories travelled by cells in the first six hours of live imaging experiments in the presence of the siRNA species indicated above each graph (only three out of the six sets of trajectories are depicted). (C) Box plots show the distributions of lengths of trajectories travelled by MCF10A cells transfected with the indicated siRNA species between t = 1 h and t = 7 h after the addition of EGF (which corresponds to t = 0 to t = 6 h of imaging). Data was obtained in three biological repeats of the experiment, in each case ten cells were manually tracked. The green and pale yellow areas correspond to the second and third quartile of the distribution, respectively. The shaded area represents the distribution of distances covered in control siGAPDH-transfected cells. P-values were obtained in a SmirnovKolomogorov test (*P,0.05 ** P,0.001). doi:10.1371/journal.pone.0049892.gin addition to “cell cycle regulation” [8]. However, by further subpartitioning GABPA targets according to regulatory mode, our study provides further insight and suggests that many of these categories are upregulated by GABPA activity. Indeed, overall the predominant mode of action for GABPA appears to be as a transcriptional activator (Fig. 2A [8]). Conversely, we show that 1407003 GABPA depletion also causes upregulation of gene expression, implying a repressive role, even in the context of direct target genes. Interestingly, several genes encoding transcriptional repressors (e.g. NCOR2, HDAC5, BCL6, BCOR) are upregulated upon GABPA depletion which might then cause some of the observed decreases in gene expression. In this study we made use of available ChIP-seq data for GABPA to distinguish between likely directly and indirectly regulated targets. While enrichment of GO term categories relating to the cytoskeleton were identified as controlled by GABPA in the entire regulome, these categories were not apparent when direct GABPA targets were analysed, suggesting that the effect of depletion of this factor on cell migration is at least partially secondary. However, importantly, we also uncovered a set ofpotential key regulators of cell migration that are direct targe.
