RNA interference (RNAi) is a powerful technique for gene silencing but the mechanisms by which double-stranded RNA (dsRNA) affects target gene activity is still poorly understood. In the Early Edition of the
Dudley et al. co-injected pools of dsRNAs into Caenorhabditiselegans embryos and screened for inhibition of RNAi-induced embryonic lethality. This led them to isolate gfl-1, a homolog of the human GAS41 gene, a predicted DNA-binding protein identified by virtue of its amplification in glioblastomas. The authors used their 'RNAi-to-RNAi' assay to test polycomb-group genes and found that polycomb-like genes mes-3, mes-4 and mes-6 were also required for RNAi. Furthermore, mutants null for these genes were also RNAi-deficient (Proc Natl Acad Sci USA ...