Evaluation of affinity purified RNA-protein complexes related with NMD

Nonsense-mediated mRNA decay (NMD) is a conserved RNA degradation pathway that is involved in development, resistance to viral infections and evolution. Upf1, a core NMD factor, is associated with a large variety of cellular RNA in complex ribonucleoprotein particles. We characterized NMD complexes previously by affinity purification of tagged protein followed by mass spectrometry. Here, we extend our observations to proteins that are present in NMD complexes, but for whom the interaction with NMD factors is mediated by RNA. We purified tagged versions of Lsm1, Lsm7, Pat1, Dhh1 and Pab1 and assessed the presence and amount of NMD and RNA-related proteins in each purification. As expected from our previously published results, Upf1 was present in these purifications, suggesting novel hypotheses about the role of Pab1 and the Lsm1-7 complexes in RNA degradation.