CCeMMP Seminar Series – Prof. Stefan Raunser – Sept 2022

Bringing life into frozen proteins to elucidate their molecular mechanisms

Prof. Raunser will focus on membrane proteins and filamentous protein complexes and present examples where interactions with small molecules have been fully characterized at atomic resolution. In particular, he will present his team’s structural work on the canonical TRPC4 ion channel and its regulation by calmodulin and pharmacological agents as well as the small molecule modulation of the Drosophila Slo channel. In addition, Prof. Raunser will highlight several F-actin structures in complex with toxins and small molecules. In the second half, he will concentrate on Tc toxins from insect-pathogenic bacteria. Tc toxins form a special protein complex that stores a “killer enzyme” in a cocoon and injects it into the cell only after contact with the host via a novel, syringe-like mechanism. There, the killer enzyme unfolds its toxic effect and leads to the aggregation of the cytoskeleton and ultimately to cell death. The team have structurally and functionally elucidated this mechanism which is of fundamental importance for the general understanding of the transport of active substances through membranes and could even be used for specific medical applications.

Professor Stefan Raunser

Department of Structural Biochemistry, Max Planck Institute of Molecular Physiology