RNA–protein interaction is an important checkpoint to tune gene expression at the RNA level. Global identification of proteins binding in vivo to mRNA has been possible through interactome capture – where proteins are fixed to target RNAs by UV crosslinking and purified through affinity capture of polyadenylated RNA. In Arabidopsis over 500 RNA-binding proteins (RBPs) enriched in UV-crosslinked samples have been identified. As in mammals and yeast, the mRNA interactomes came with a few surprises. For example, a plethora of the proteins caught on RNA had not previously been linked to RNA-mediated processes, for example proteins of intermediary metabolism. Thus, the studies provide unprecedented insights into the composition of the mRNA interactome, highlighting the complexity of RNA-mediated processes.
We thank Prof. Michael Ladomery for comments on the draft of this manuscript. We gratefully acknowledge support by the Deutsche Forschungsgemeinschaft (DFG) through grants STA653 and SPP1530. C.M. was funded by the Office of Competitive Research Grant Program, grant CRG3-62140383, from King Abdullah University of Science and Technology (KAUST). K.M. was funded by the German National Academic Foundation.