Project A01

 

Elke Deuerling

Role of ribosome-associated Hsp70/Hsp40 chaperones in proteostasis

In this project we will investigate the functions and mechanisms of the eukaryotic ribosome-associated Hsp70/Hsp40 chaperone system (RAC-Ssb in yeast). The RAC-Ssb system transiently binds to cytosolic ribosomes and Ssb interacts with nascent polypeptides to guide early protein folding processes. A major goal is to understand how the synthesis of polypeptides is physically and functionally coordinated with the activity of RAC-Ssb on ribosomes. Furthermore, the yeast Hsp70 Ssb executes another crucial function by supporting de novo assembly of ribosomal subunits in the nucleus. Thus, another goal is to investigate how Ssb acts during the assembly of preribosomal particles in the nucleus and clarify if RAC is important for this function. Finally, we will address the question if these fundamental roles of the Hsp70/Hsp40 system in proteostasis are specific for yeast or evolutionarily conserved in higher eukaryotes.