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 Proceedings of the National Academy of Sciences, Nathaniel Dudley and colleagues from the University of North Carolina at Chapel Hill describe a method for isolating dsRNA molecules that prevent RNAi and give insights into the mechanisms involved. They co-injected pools of dsRNAs into Caenorhabditis elegans 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. Further work will be required to understand the role of these chromatin-binding factors in the mechanisms of RNAi.

[Read the abstract on PubMed]


Proceedings of the National Academy of Sciences
http://www.pnas.org


University of North Carolina
http://www.unc.edu


Using RNA interference to identify genes required for RNA interference
http://www.pnas.org/cgi/doi/10.1073/pnas.062605199

Author: Jonathan B Weitzman
jonathanweitzman@hotmail.com