Summary

The architecture and function of each cell relies entirely on the correct folding, assembly and localisation of its constituent proteins. From the onset of protein synthesis until the end of the lifecycle, a polypeptide has to establish and maintain a biological active three-dimensional structure. Throughout all kingdoms of life, a set of conserved folding helper protein, collectively termed molecular chaperones is of vital importance for this process. No cellular compartment can be formed without their action. One of the most remarkable features of molecular chaperones is their ability to recognize and bind nonnative proteins, thus preventing their unspecific aggregation. In addition, to maintain protein homeostasis under physiological and under stress conditions, molecular chaperones are also involved in regulating the activity of specific client proteins. Modulation of protein structure also plays an important role in the trafficking and distribution in every cell no matter if eukaryotic or prokaryotic. Protein targeting and translocation involves the action of energy dependent multi-subunit nanomachines and intracellular tracks (highways) for the biogenesis of organelles like mitochondria or chloroplasts as well as the endomembrane system. To understand how for example a eukaryotic cell manages to synthesize simultaneously proteins for ten different cellular or extracellular compartments at the same time and to obtain their correct distribution and fold is a central question in molecular cell biology. We will address these fundamental aspects using a combination of biochemical, biophysical and structural techniques in vitro in combination with in vivo techniques like life cell imaging or forward and reverse genetics. We are planning to establish a strong link with groups working on the physics of protein folding (area A, Zinth) and misfolding disease (area F). Regarding the molecular motors we plan to link up with the groups of Rief (area A).