Jan Riemer

FMNS | Institute of Biochemistry (UoC)

Prof. Dr. Jan Riemer CECAD Cologne
Prof. Dr. Jan Riemer

Principal Investigator

Research Areas

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Mitochondrial Redoxbiology

Mitochondria are tightly integrated into cellular signalling networks. Major signalling processes are thereby driven by redox molecules. We analyze redox processes and their impact on signalling and on mitochondrial biogenesis.

Research Focus

Redox reactions are at the center of most cellular processes: they are the mechanistic basis of metabolic pathways, they contribute to proteostasis, e.g. by the introduction and removal of disulphide bonds, and they drive the production of reactive oxygen species (ROS), which - with their Janus-faced character of being on the one hand toxic and on the other essential for signalling - impact heavily on cellular physiology. A number of diseases have been directly linked with dysregulated redox homeostasis, including cancer, neurological disorders, cardiovascular diseases, obesity and metabolic diseases, as well as aging.

Redox processes are at the core of most cellular processes and we aim to understand their contribution to the regulation and flawless functionality of these processes

Our Goals

We have characterized novel pathways for protein import into the mitochondrial intermembrane space, and we have investigated the crosstalk of mitochondrial protein import, redox regulation, and metabolic processes in the intermembrane space.

Our goal is to understand in molecular detail the mechanisms and regulation of mitochondrial biogenesis and mitochondrial communication with the remainder of the cell. We aim to understand in molecular detail:

  • How redox homeostasis is maintained in the different compartments of a cell;
  • How mitochondria as major ROS generators are integrated into cellular signalling networks;
  • How redox processes drive mitochondrial biogenesis;
  • How organellar proteome plasticity is driven by metabolic and redox changes, e.g. during cell differentiation.

We employ a combination of biochemical and cell biological methods ranging from in vitro reconstitution experiments of whole enzymatic cascades, via different proteomics approaches to tackle specific redox changes and complex assembly processes, genetic screens using CRISPR-Cas technology, to the application of genetically encoded sensors and engineering tools. As model systems, we rely on mammalian cell culture, on mice and baker’s yeast.

Key Publications


  1. Peker E, Weiss K, Song J, Zarges C, Gerlich S, Boehm V, Trifunovic A, Langer T, Gehring NH, Becker T, Riemer J. (2023) A two-step mitochondrial import pathway couples the disulfide relay with matrix complex I biogenesis, J Cell Biol. 222(7):e202210019.
     
  2. Nanadikar MS, Vergel Leon AM, Guo J, van Belle G, Jatho A, Brandner A, Böckmann R, Rhunzu S, Brodesser S, Schmidtendorf M, Lee J, Wu H, Furdui C, Burgoyne J, Bogeski I, Riemer J, Chowdhury A, Rehling P, Bruegmann T, Belousov V, Katschinski D (2023) IDH3γ serves as a redox switch that regulates mitochondrial energy metabolism and contractility in the heart under oxidative stress. Nature Communications 14(1):2123
     
  3. Salscheider SL*, Gerlich S*, Cabrera-Orefice A*, Peker E, Rothemann RA, Murschall LM, Finger Y, Szczepanowska K, Ahmadi ZA, Guerrero-Castillo S, Erdogan A, Becker M, Ali M, Habich M, Petrungaro C, Burdina N, Schwarz G, Klußmann M, Neundorf I, Stroud DA, Ryan MT, Trifunovic A, Brandt U, Riemer J. (2022) AIFM1 is a component of the mitochondrial disulfide relay that drives complex I assembly through efficient import of NDUFS5. EMBO J. e110784
     
  4. Li X, Straub J, Medeiros TC, Mehra C, den Brave F, Peker E, Atanassov I, Stillger K, Michaelis JB, Burbridge E, Adrain C, Münch C, Riemer J, Becker T, Pernas LF (2022) Mitochondria shed their outer membrane in response to infection-induced stress Science 375(6577)_eabi4343
     
  5. Hoehne MN, Jacobs LJHC, Lapacz KJ, Calabrese G, Murschall LM, Marker T, Kaul H, Trifunovic A, Morgan B, Fricker M, Belousov VV, Riemer J, (2022) Spatial and temporal control of mitochondrial H2O2 release in intact human cells. EMBO J, e109169
Prof. Dr. Jan Riemer CECAD Cologne
Prof. Dr. Jan Riemer

Principal Investigator

Research Areas

1
2
3