Doctoral researcher positions in Protease Research (m/f/d)

P2: Dr. Ruth Geiss-Friedlander: Investigating DPP9 regulation, substrate recognition, and non-catalytic functions

Proteolytic processing is a key regulatory mechanism in cell biology, with N-terminal sequences playing central roles in post-translational regulation. The intracellular protease DPP9 is unique in its ability to remove N-terminal dipeptides after proline (Xaa-Pro-↓Zaa). DPP9 has been shown to play a role in immune regulation, metabolism, and DNA repair, and its dysregulation is linked to cancer and immune disorders (reviewed in Zolg et al. 2024).

Despite its physiological importance, only a limited number of DPP9 substrates and interaction partners have been characterized. In addition to its catalytic activity, DPP9 also has non-enzymatic functions through protein interactions, highlighting the need to better understand the mechanisms regulating its activity and binding partners.

This project aims to uncover how DPP9 is regulated, identify the determinants of DPP9–substrate interactions, and define its non-catalytic functions. It offers an excellent opportunity for a motivated doctoral candidate interested in molecular cell biology, biochemistry, protein interaction networks, protease activity and regulation. For more information, visit our website.

P4: Prof. Dr. Georg Häcker: Determine the role of sub-lethal caspase-activity in primary cells

Caspases are best known for their role in apoptosis. However, although many hundreds of substrates of caspase-3 have been described, there is arguably not a single one whose role in apoptosis is in fact clearly established. We have been working on sub-lethal signaling in the apoptosis pathway and have found that caspases are active at a sub-lethal level in at least many non-apoptotic cells at homeostasis. We have identified two situations where sub-lethal substrate cleavage has physiological effects in the regulation of signal transduction. In these cases, caspase-mediated proteolysis regulates cellular signaling pathways. We have identified more substrates of at this stage uncertain significance. This project will continue with substrate identification of effector caspases in non-apoptotic cells and with the assessment of the biological role of sub-lethal caspase activity in various mammalian cell types.

P9: Prof. Dr. Thomas Reinheckel: Function and substrates of aminopeptidases during myelopoiesis.

Aminopeptidases remove one or few amino acids from the N-terminus of proteins or peptides. Although this is an apparently minor modification, it can have significant effects on the stability and function of the cleaved protein. Moreover, aminopeptidases are more and more known to function by non-catalytic interactions with other proteins. In recent years, the impressive improvements in proteomic technologies are now allowing the analysis of the complex N-terminome and the protein-protein interactome of cells and tissues. By using genetic models, we recently found that these aminopeptidases have strong impact on the differentiation of murine hematopoietic stem cells to bone marrow derived macrophages and possibly other bone marrow derived immune cells. The PhD project will explore the details of those differentiation defects, while simultaneously uncover their molecular basis with help of proteomics and single cell technologies.

Doctoral researcher (m/f/d) positions in Protease Research in Freiburg with a 3-year contract duration (Salary scheme E13 TV-L; 65%).

Applicant requirements:

We are looking for highly motivated doctoral candidates in life sciences of all nationalities who are strongly committed to basic and translational research. A Master of Science degree is required to enter the program.

If you want to join us, check for individual project descriptions, how-to-apply, and learn more about GRK 2606 on:

https://www.protpath.uni-freiburg.de/

Starting times are January 2027 (P2, P9) and March 2027 (P1, P4).

Application/documents required:

• CV, Personal data/contact details
• Bachelor and Master degrees (or equivalent) - transcripts and certificates
• University entrance qualification certificate and transcript
• Proof of English proficiency (German Abitur is eligible as proof)
• 2 reference letters
• Motivation letter and research interest - You will select here the project you want to apply for, and will be able to indicate a second preference

Please provide all required documents as one merged .pdf file.

Application deadline: October 15th, 2026

Please apply online via the “apply now” button.

Dr. Susanne Elfert, Institute for Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg, Stefan-Meier-Straße 17, 79104 Freiburg.

General information: Salary is assigned according to a pay scale. Unless prevented by operational or legal reasons, full-time positions are generally open to those wishing to job share. Where two candidates are equally suitable for a post, severely disabled candidates are given priority. Employment decisions are made by the Personnel Department.