Research

We are interested in understanding ribosomal structure and function in all kingdoms of life. Using a combination of biochemical, crystallographic and electron microscopic experiments we have obtained insights into co-translational nascent chain folding, processing and targeting to the membranes. Our recent focus is to understand eukaryotic cytoplasmic and mitochondrial ribosomes and their functional complexes involved in regulation and initiation of protein synthesis. Ultimately we intend to obtain a “molecular movie” of these processes at high resolution so that they can be understood at a detailed mechanistic level.

Eukaryotic Cytosolic Ribosomes

The eukaryotic protein synthesis machinery is much more complex than in bacteria. We have revealed the unique architectural features of eukaryotic ribosomes and are currently investigating the eukaryotic-specific mechanisms of translation initiation, ribosome assembly, and targeting of proteins to membranes.

Mitochondrial Protein Synthesis

Mitochondria and chloroplast organelles in eukaryotic cells originated from free-living bacterial ancestors. Whereas ribosomes in chloroplasts are structurally still closely related to their bacterial ancestor, mitochondrial ribosomes diverged considerably during evolution, as visualized by our group for mammals and trypanosomes.

Co-translational Targeting, Processing and Folding

With the aim to better understand the molecular machinery involved in co-translational protein targeting, processing, and folding of proteins we investigate ribosomal complexes with chaperones, nascent chain processing enzymes, the signal recognition particle, and the translocon.

Ribosome Assembly

During biogenesis of the ribosome, ribosomal proteins and RNAs have to correctly assemble. In eukaryotes, ~200 assembly factors support this process and additionally cleave and/or modify the RNA. We are interested in understanding the underlying mechanisms.

Large Assemblies

We are generally interested in understanding the structure and function of large cellular assemblies and multifunctional enzymes including mammalian target of rapamycin (mTOR), the fatty acid synthase, as well as natural and bio-engineered encapsulation systems and pore-forming toxins.

Nomenclature of Ribosomal Proteins

To eliminate historical naming discrepancies between ribosomal proteins from different species, a consortium of structural biologists and biochemists are using a new naming system that is universally applicable. Conversion tables and PyMOL scripts and sessions for visualization are found here.