Figure 6

Ku70 is recruited to the ERBB2 promoter and is necessary for the recruitment of AP-2 and of RNA PolymeraseII. (a) Chromatin extracted from BT-474 cells transfected or not with AP-2 (αγ) or Ku70 siRNAs (above) was shared by sonication to fragments of 100-500 bp. Protein expression was verified by immunoblot. (b) Schematic representation of the ERBB2 promoter illustrating the amplified regions. (c) DNA amplified after chromatin immunoprecipitation with AP-2, Ku70 and RNA Polymerase II (Pol II) specific antibodies. ChIP with control antibodies (Ig) are presented on the left of each experimental point (R: rabbit, G: goat and M: mouse). Graphs show the fold enrichment of the target sequence, compared to the no-antibody (NoAb) condition. The error bars were calculated from the results of three independent ChIP experiments. GCK sequence corresponds to a positive control for Ku recruitment. * and **: P-values < 0,05% compared to the No siRNA condition.