PhD student (m/f/d)
- Cell competition in 3D embryonic models (Gastruloids) -
Deadline to apply: 29.04.2026
Our Research focus:
During early embryonic development, suboptimal cells need to be detected and eliminated to ensure that only the fittest cells participate in forming the body. In part, this is achieved through a process called Cell Competition, in which neighboring cells compare their relative fitness to each other, after which lesser fit cells undergo cellular suicide by apoptosis. We recently characterized this process in detail using gastruloids, a 3D embryonic stem cell-based in vitro system that recapitulates the core machineries of embryonic development from the blastocyst up to somitogenesis (Frenster et al., Nature Cell Biology 2026). The open questions in the field are now: 1) how do the cells communicate with each other in this process? 2) Are the mechanisms we found in mouse developmental systems also is true in human development? 3) And lastly, do species with altered quality control mechanisms and cancer resistance differ in their cell competition behavior?
To answer these questions, we perform high-throughput genetic and pharmacological screens in 3D mouse gastruloids and combine the results with time-resolved transcriptomics to find the communication mechanisms between competing cells. Further, we develop a new model of naïve human 3D gastruloids to finally bring the cell competition field into human development, and lastly, we are using iPSCs of cancer resistant species (naked mole rat iPSCs; elephant iPSCs) to generate their first in vitro 3D developmental models and study the interplay between cancer resistance pathways and developmental fidelity.
PhD Candidates must have:
MSc in developmental-, stem cell-, cancer biology, or a related field
Experience with cell culture and wet lab experiments as well as scientific writing skills
High rigor, independence, and collaborative mindset
Be comfortable discussing and writing about research in English language
Experience that would be beneficial but not required:
3D cell culture systems (gastruloids, organoids)
2D Stem cell culture (mouse or human)
Flow cytometry
Microscopy and simple image analysis
Molecular cloning, CRISPR KO generation
RNA-seq/NGS workflows and/or analysis (R/Python)
What we offer:
As a founding member of this new Emmy Noether group, the PhD student will benefit from close and direct mentorship with high temporal dedication from the group leader. This mentorship, while close at the start, has the explicit goal of building scientific independence, hoping that PhD student grow into a role of confidence to present research at conferences and supervise Master’s students at later stages of the PhD. The student will additionally have the freedom to help explore and establish new techniques together with the group leader with the hope to expand their own scientific “toolbox” over time, while working on an ambitious and high-impact project. Depending on the project fit, the work may range from large semi-automated discovery screens, mechanistic dissection of cell-cell communication pathways, to cutting-edge 3D developmental models using human embryonic stem cells, or establishing the first developmental 3D system using cancer resistant naked mole rat stem cells. Our group is embedded in the excellent infrastructure of the University of Freiburg and located in the Signalhaus within the CIBSS Cluster of Excellence. The position is fully funded for the entire duration of the PhD under DFG guidelines. Students are encouraged to apply for own fellowships during this time with the help of the group leader, which will help develop their CV.
Apply:
Deadline 29.04.2026. Please submit as one PDF file: a short cover letter describing your background and interest in our group, a CV including your education and research experience, and contact details of 2 references. Send this PDF with the subject line “Application PhD Cell Competition” to
Joshua.frenster@gmail.com
