About
Head: Prof. Stefan Müller
Ubiquitin and Ubiquitin-like protein modification systems control a wide variety of cellular key processes. Our laboratory is studying mechanistic and functional aspects of the Ubiquitin-like SUMO system in mammalian cells. SUMO (Small Ubiquitin-like Modifier) functions as a post-translational modifier that is covalently attached to lysine residues of target proteins. Human cells express three SUMO forms, which are conjugated in a pathway that requires the E1 activating enzyme Aos1/Uba2, the E2 conjugating enzyme Ubc9 and in many cases involves E3 SUMO ligases.
SUMO modification is a dynamic, reversible process, in which the demodification of a given SUMO-conjugate is catalyzed by SUMO-specific proteases of the SENP family.
SUMO conjugation/deconjugation typically modulates protein-protein interactions thereby controlling cellular key pathways, including gene expression programs, ribosome biogenesis, mitotic progression or genomic integrity.
Signaling by SUMO generally relies on the recognition of a modified protein by a binding partner that contains a specialized SUMO binding module termed SUMO interaction motif (SIM).
However, a detailed understanding of SUMO function in most pathways is still incomplete because the relevant targets of modification and the corresponding SUMO-dependent binding partners have not been identified. In our work we therefore want to pinpoint the critical targets of SUMO in selected cellular pathways and aim to understand the dynamics of SUMO/SIM interactions.
Members
Lab Members
Prof. Stefan Müller
Stefan Müller studied pharmacy at Ludwig-Maximilians-University Munich and obtained his diploma and approbation in 1991. He subsequently worked as a PhD student and research assistant in the Institute of Physiological Chemistry under the supervision of Hans Joachim Seitz at Hamburg University, where he graduated in 1995. With a Marie-Curie post-doctoral fellowship from the EU he joined the laboratory of Anne Dejean at Pasteur Institute, Paris. Here he discovered the post-translational modification of PML by the ubiquitin-like SUMO modifier. He continued investigating the SUMO system and in 2001 became independent group leader at the Max Planck Institute of Biochemistry, Munich-Martinsried, in the Department of Stefan Jentsch. In 2010 he was appointed professor of biochemistry at Goethe University Frankfurt and since 2016 is the acting managing director of the Gustav-Embden-Center for Biological Chemistry. Link to Vice-Director page.
Jan Keiten-Schmitz
Jan Keiten-Schmitz was born in Freiburg, Germany. He studied Biology in Darmstadt and Heidelberg and obtained his diploma degree in 2013. In his diploma thesis he studied the TOM complex of Leishmania tarentolae.
In September 2013 he started his PhD in the lab of Stefan Müller at the IBCII. Jan is studying the SUMO-targeted E3 ubiquitin-protein ligases (STUbLs) RNF4 and RNF111.
Hannah Mende
Hannah Mende studied Molecular Biology (B. Sc.) and Biomedicine (M. Sc.) at the JGU in Mainz and obtained her degree in 2017. In her Master´s thesis she studied RNAs associated to extracellular vesicles and the involvement of RNA binding proteins in RNA sorting mechanisms. In July 2017 she joined Stefan Müller´s group at the IBCII in Frankfurt to study the involvement of SUMOylation in autophagy within the SFB 1177.
Paul Hotz
Paul grew up in Essen and graduated from school in Wiesbaden with general qualification for university entrance (Abitur). He studied medicine at Goethe-Universität Frankfurt am Main and obtained the 1.Staatsexamen in summer 2017. Since September 2017 he started his MD Thesis in the SUMO signalling Group of Stefan Müller at Institute of Biochemestry II. He is now focussing on the role of SUMO system during cardiac ischemia/reperfusion injury and the identification of novel SUMO targets via mass spectrometry.
Kathrin Kunz
Kathrin grew up in Saarland where she completed her education in schools with the general qualification for university entrance (Abitur). She then moved to Kaiserslautern to study Food Chemistry and finally obtained her diploma degree (food chemist) in March 2014.
For her diploma thesis she worked in the group of Melanie Esselen where she investigated the influence on redox-sensitive genes from extracts of traditional Chinese foodstuff and other model substances.
Subsequently Kathrin started her PhD in the group of Stefan Müller at the Institute of Biochemistry II in Frankfurt. Since July 2014 she is focusing on redox regulation of the SUMO system.
Dr. Luca Mendler
Luca Mendler was born in Baja, Hungary. She studied medicine at the University of Szeged, Hungary and obtained her diploma in 1997. During her PhD she analyzed the molecular regulation of skeletal muscle regeneration at the University of Szeged as well as the Catholic University of Leuven, Belgium. After completing her PhD thesis in 2000, she kept on working on the molecular mechanisms regulating skeletal and cardiac muscle growth in the Institute of Biochemistry, Szeged (2000-2004). As an assistant professor she was teaching biochemistry for Hungarian, English and German medical students for several years as well (2004-2014). In 2008-2009 she received a scholarship of the Max Planck Society for deciphering the cell-autonomous role of the growth regulator myostatin in the heart in the Max-Planck-Insitute for Heart- and Lung Research, Bad Nauheim, Germany. In 2014 she joined to the Institute of Biochemistry II at the Goethe University, Frankfurt and has been involved in various teaching activities for medical students. She also started to work in the group of Stefan Müller analyzing the role of SUMO modification in the heart, more specifically, the possible function&redox regulation of SUMOylation during cardiac ischemia/reperfusion injury.

Kristina Wagner