An RNAi screen of the RRM-domain proteins of Trypanosoma brucei.

In eukaryotes, proteins containing RNA Recognition Motifs (RRMs) are involved in many different RNA processing reactions, RNA transport, and mRNA decay. Kinetoplastids rely extensively on post-transcriptional mechanisms to control gene expression, so RRM domain proteins are expected to play a prominent role. We here describe the results of an RNA interference screen targeting 37 of the 72 RRM-domain proteins of Trypanosoma brucei. RNAi targeting 8 of the genes caused clear growth inhibition in bloodstream trypanosomes, and milder effects were seen for 9 more genes. The small, single-RRM protein TbRBP3 specifically associated with 10 mRNAs in trypanosome lysates, but RBP3 depletion did not affect the transcriptome.