Why? This paper reports the results of a small-scale Drosophila RNAi screen the authors based on a set of candidate genes; namely, SCF-class ubiquitin ligases. The authors designed and generated dsRNAs for RNAi experiments targeting 58 genes in that family, and conducted their screen on those 58 targets.
By focusing in on a small set of candidates, the researchers were able to go into enviable depth in at least these two ways: first, they did not one but two sequential primary assays; and second, their further analysis of hits included to assess knockdown at the protein level for those genes for which antibodies were available.
Technical notes: the authors used EGFP and mCherry markers, live cell imaging, and induction of cell cycle arrest (S phase, G2 phase or mitosis) with drug treatments. Imaging with S2 cells plated on Con-A coated glass-bottom 6-well dishes. Analyses included FACS, fluorescence microscopy and EM.