Postdoctoral Fellow (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 creating the body. To achieve this, cells undergo a process called Cell Competition, in which neighboring cells compare their relative fitness to each other, after which, cells that are less fit than their neighbors 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 aspects of embryonic development from the blastocyst- up to somitogenesis stage (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 murine developmental systems also true in human development? 3) And, 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 our results with time-resolved transcriptomics to find the communication mechanisms between competing cells. Further, we develop a new model of 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.
Postdoc Candidates must have:
PhD in developmental-, stem cell-, cancer biology, or a related field
Strong experimental background and scientific writing skills
High rigor, independence, and collaborative mindset
Be comfortable discussing and writing about research in English language
Experience nice to have but not required:
2D stem cell culture (mouse or human) and 3D culture systems (gastruloids, organoids)
Flow cytometry
Microscopy and simple image analysis
Molecular cloning, CRISPR KO generation
RNA-seq/NGS workflows and/or analysis (R/Python)
The Position:
As a founding member of this new Emmy Noether group, the postdoc will be able to drive an ambitious and high-impact project, while obtaining close mentorship from the PI with the explicit goal of building scientific independence. The postdoc will be offered supervision roles for students in order to develop their own mentoring and leadership skills, and will be supported to present results at conferences to build their own network. 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 the CIBSS Cluster of Excellence. The position is fully funded for the first 12 months under DFG guidelines, with the expectation to apply for own fellowships during this time.
Earliest start date: July 1, 2026; later start dates in the fall are possible upon agreement with the PI.
Apply:
Deadline: 29 April 2026.
Note: All applications will be reviewed after the deadline. If you do not hear from the PI before then, this is part of the normal review process and not indicative of your application status.
Please submit a single PDF file containing:
a short cover letter describing your background and interest in our group,
a CV including your publication record, and
contact details for two references.
Name the file “Application_Postdoc_[YourName].pdf” and send it with the subject line “Application Postdoc Cell Competition” to:
Joshua.frenster@gmail.com
