Talk by Johannes M. Herrmann
Title: "Mitochondrial protein biogenesis: A big challenge for eukaryotic cells"
Occasion: SFB Seminar
Host: Christian Ungermann
Start: 12.05.2022 - 16:15
Location: CellNanOs 38/201
About the speaker: Johannes M. Herrmann heads the group Cell Biology, University of Kaiserslautern.
Abstract of the talk: Most mitochondrial proteins are synthesized as cytosolic precursor proteins before they are imported into mitochondria. The molecular details of the mitochondrial import reactions were dissected in great mechanistic detail by the use of very powerful biochemical methods in vitro. However, recent in vivo studies by us and others showed that mitochondrial precursor proteins have a surprisingly complex biology before they reach the mitochondrial surface. We realized that mitochondrial precursor proteins explore the cytosol, get in contact with components of the proteasome and chaperone network and often end up on the surface or even the lumen of other cellular compartments. Under conditions of reduced mitochondrial protein uptake, these cytosolic precursor proteins pose a severe threat to cytosolic proteostasis. And vice versa, improving mitochondrial protein import can suppress the proteotoxic effect of aggregation-prone proteins in the cytosol. Thus, mitochondrial precursors are central constituents of the cytosolic proteostasis network and to deal with these proteins is a big challenge for eukaryotic cells. In my talk, I will give an overview about our current knowledge of these early reactions in mitochondrial protein targeting and present recent data from our team.