Gene- and species-specific Hox mRNA translation by ribosome expansion segments

Ribosomes have been suggested to directly control gene regulation, however regulatory roles for ribosomal RNA (rRNA) remain largely unexplored. Expansion segments (ESs) consist of multitudes of tentacle-like rRNA structures extending from the core ribosome in eukaryotes. ESs are remarkably variable in sequence and size across eukaryotic evolution with a largely unknown function. In characterizing ribosome binding to a regulatory element within a Homeobox (Hox) 5’ UTR, we unexpectedly identify a modular stem-loop within this element that binds to a single ES, ES9S. Here, we described the raw data of the relative quantification proteomic analysis using tandem mass tag mass spectrometry of the ribonucleoprotein (RNP) complexes enriched from affinity pulldown of the 4xS1m-aptamer fusion constructs with the lysate components of C3H/10T1/2 cells and mouse embryo. 4xS1m pulldown is performed by combining mouse Hoxa9 mRNA elements (P3 and P4) with C3H/10T1/2 cell lysates, and by combining a9 IRES180 and an unrelated viral IRES with E11.5 FVB mouse embryo lysates. The aptamer alone served as a negative control. RNPs in the eluate were released by RNAse A treatment and were subjected to TMT 6plex labelling.