University of Minnesota
School of Physics & Astronomy

Physics and Astronomy Calendar

Thursday, October 24th 2019
10:10 am:
Biophysics Seminar in 120 PAN
Speaker: Rayna Addabbo, UMN
Subject: The complementary role of co- and post-translational events in de novo protein synthesis

While required for life, protein folding is poorly understood, especially in the context of the complex environment of the cell. Here, I report recent findings on the relationship between co- and post-translational protein folding and protein aggregation. I show that the ribosome promotes cotranslational nascent-protein solubility, thus supporting cotranslational folding even in the absence of molecular chaperones. The ribosome alone, however, does not guarantee quantitative formation of the native state. Upon completion of protein biosynthesis, there is a crucial irreversible post-translational kinetic partitioning between protein folding and protein aggregation. De novo-synthesized proteins only attain their native state if the rates of soluble and insoluble aggregate formation upon release from the ribosome are slow relative to intramolecular folding. Mutational analysis demonstrates that the above post-translational kinetic partitioning events are more sensitive to amino-acid sequence than the native fold, suggesting post-translational kinetic partitioning is a source of significant evolutionary pressure.

The weekly calendar is also available via subscription to the physics-announce mailing list, and by RSS feed.