Molecule of the Month
February 2020
Embrace Your Friends: Ribosomal RNA Expansions Recruit
Protein-Modifying Enzymes to the Translation Machinery

During evolution the ribosomal RNA acquired expansions at the periphery of the ribosome. Even though the locations of these RNA expansion segments (ES) within the ribosome are highly conserved, its functions are poorly understood.
Here we could demonstrate that one particular ES in the yeast ribosome recruits two enzymes (NAT and MAP) that co-translationally modify the new born proteins. Removal of this ES does not affect the ribosomes principal capacity to synthesize polypeptides but leads to a markedly altered proteome with increased protein aggregation propensity.

This work was carried out by Vaish Shankar, Robert Rauscher & colleagues in the group of Prof. Norbert Polacek.


  • V. Shankar, R. Rauscher, J. Reuther, W. H. Gharib, M. Koch, N. Polacek;
    "rRNA expansion segment 27Lb modulates the factor recruitment capacity of the yeast ribosome and shapes the proteome"
    Nucleic Acids Research, 2020, 48(6), 3244-3256; doi:10.1093/nar/gkaa003.