GBM Awards Event

Abstract Michael Ameismeier

Small ribosomal subunit complexes visualized by cryo-EM

Ribosomes are key components of the cellular machinery responsible for protein synthesis. These macromolecular complexes consist of two subunits, each comprising ribosomal RNA and multiple proteins. Due to their central biological role in protein production, correct formation and functioning of new ribosomes is critical for the survival of all biological systems. Using cryo-electron microscopy, we were able to follow the small ribosomal subunit along its maturation pathway. Based on structural models of several assembly intermediates, we derived common principles that define the final steps in small subunit formation. Furthermore, high-resolution information on several accessory proteins, which guide the correct folding of rRNA and incorporation of ribosomal proteins, allowed a detailed description of regulatory interactions between the ribosome and its assembly factors. Finally, in a second project, we analysed the binding of Nsp1 to a fully matured ribosome. Nsp1 is a protein of the novel SARS Coronavirus and its presence leads to a shutdown of translation and thus prevents an effective immune response of an infected host cell.