Suppression of G1 arrest by simultaneous knockdown of Dacapo is protein complex-specific. S2R+ cells were treated with dsRNAs targeting the indicated members of the COP9 signalosome, proteasome lid or eIF3 protein complex in combination with either dsRNA targeting GFP (light grey) or Dacapo (dark grey). The percentage of cells with G1 DNA content was determined by flow cytometry. Error bars are standard error of three replicates. Results for additional subunits of these complexes as well as other genes that produced a G1 arrest upon knock down are shown in Additional File 8.