## **Do you want to contribute to top quality medical research?**

The Stagkourakis and Nyberg Labs, located in state‑of‑the‑art facilities at the interface of Karolinska Institutet (KI) and SciLifeLab in Stockholm, are recruiting a postdoctoral researcher to work on the development of Fast, Light‑And‑State‑gated, Retro‑Orbital AAVs to Tag & Control Neural Ensembles, an interdisciplinary project jointly led by Stefanos Stagkourakis and William Nyberg and supported by the KI research incubator program (KIRI).

The Stagkourakis labs is embedded in the Dept. of Neuroscience at Karolinska Institutet and is part of SciLifeLab, a Swedish national center for large‑scale molecular biosciences and cutting‑edge infrastructure. Our research focuses on the neural basis of prototypical behaviors, including aggression, defensive states, and parental care, using a combination of advanced behavioral paradigms, *in vivo* recordings, and circuit manipulations.

The Nyberg Lab, based at the Department of Medicine, Huddinge and SciLifeLab, develops evolved AAV capsids and state-controlled gene-expression technologies for *in vivo* viral engineering. This project brings the two laboratories together to build a shared experimental platform that neither lab could develop alone.

The postdoc will be primarily based in the Stagkourakis Lab for day-to-day experimental work, but will be fully embedded in both laboratories, with structured co-mentorship from Nyberg and regular integration into both research environments. For more information on the Stagkourakis Lab see here, and for the Nyberg Lab see here.

### **Division**

The Department of Neuroscience at Karolinska Institutet hosts ~20 research groups working on fundamental and disease‑related aspects of nervous system function: https://ki.se/en/neuro/research/group-leaders-at-the-department-of-neuroscience

SciLifeLab is a national research infrastructure providing unique technologies and expertise in molecular biosciences, closely integrated with the KI research community and partner universities.

The position is part of a long‑term interdisciplinary collaboration with Dr William Nyberg, Assistant Professor at the Department of Medicine, Huddinge, and SciLifeLab, whose group develops evolved AAV capsids and optically controlled gene‑expression systems for *in vivo* cell engineering. The successful candidate will help consolidate and expand this joint platform.

### **Your mission**

You will be the lead experimental postdoc on a project at the interface between viral engineering and systems neuroscience. Your main responsibilities will include:

- Developing and implementing a dual‑AAV system for red‑light‑ and activity‑dependent transgene expression in the adult mouse brain (design and testing in close collaboration with the Nyberg Lab).
- Performing retro‑orbital AAV delivery, stereotaxic surgeries, and fiber/GRIN lens implants.
- Designing and running behavioral paradigms, with a focus on resident–intruder aggression and related instinctive behaviors.
- Recording neural activity using miniscope imaging or two‑photon microscopy (head‑fixed and freely moving setups), and combining this with optogenetic manipulations.
- Coordinating viral production/testing with the Nyberg Lab and establishing robust SOPs for the toolkit.
- Analyzing experimental data using existing pipelines (Python/MATLAB) and interacting with computational collaborators for more advanced state‑space / network analyses.
- Disseminating results via manuscripts, conference presentations, and internal seminars; co‑mentoring students and research assistants as appropriate.

This role is fundamentally integrative: your work will operate across both labs’ strengths, helping develop a unified research pipeline that spans viral design to systems-level circuit interrogation.

**Candidate’s profile**

We are looking for a curious, hands‑on experimentalist who enjoys working across methods and disciplines. Required qualifications and experience:

- A PhD (or equivalent) in neuroscience, biomedical sciences, bioengineering, or a closely related field, obtained no more than a few years before the start date (according to KI postdoc rules).
- Strong experience in *in vivo* rodent experiments, with competence in at least one of: Stereotaxic surgery and viral/vector delivery, *in vivo* imaging (miniscope, 2P), optogenetics/chemogenetics in behaving animals.
- Design and execution of behavioral paradigms in mice.
- Demonstrated scientific productivity, typically through first‑author publications or equivalent outputs.
- A high degree of independence, good organizational skills, and strong communication in English (spoken and written).
- Strong social skills and ability to work both independently and to be part of teams – all aspects necessary for this role.

Candidates with demonstrated expertise in one or more of the following are particularly encouraged to apply:

- AAV or lentiviral work (design, preparation, or *in vivo* use).
- Integration of behavior with imaging/optogenetics in mice.
- Development of custom behavioral tasks and closed‑loop experimental designs.
- Proficiency in basic data analysis in Python or MATLAB (more advanced modeling will be supported by collaborators).
- Prior work in collaborative, interdisciplinary projects.

Most importantly, we value enthusiasm for learning new techniques, the ability to troubleshoot complex experiments, and an interest in understanding how survival circuits are organized and controlled.

### **Your profile**

To be eligible for employment as a postdoctoral researcher, a PhD or a foreign degree deemed to be equivalent to a Swedish PhD is required. This eligibility requirement must be fulfilled at the latest at the time of the employment decision. Completion of your doctoral degree within the last three years is considered an advantage. If there are special reasons, your degree may have been completed earlier.

### **What do we offer?**

A creative and inspiring environment with wide-ranging expertise and interests. Karolinska Institutet is one of the world's leading medical universities. At Karolinska Institutet, we conduct successful medical research and hold the largest range of medical education in Sweden. At KI, you get to meet researchers working with a wide range of specialisms and methods, giving you ample opportunity to exchange knowledge and experience with the various scientific fields within medicine and health. It is the crossover collaborations, which have pushed KI to where it is today, at the forefront of global research. Several of the people you meet in healthcare are educated at KI. A close relationship with the health care providers is important for creating groundbreaking top quality education and research. Karolinska Institutet is also a state university, which entitles you to several benefits through our collective agreement.

We provide a creative and collaborative environment with wide‑ranging expertise: A joint supervision structure where you are primarily based in the Stagkourakis Lab (behavior, imaging, systems neuroscience) with co‑mentorship from the Nyberg Lab (AAV engineering, optogenetic gene control). Access to:

- Fully equipped behavior rooms and animal facilities (KM‑B/KM‑F).
- Two‑photon microscope with SLM module, Inscopix miniscope, and fiber‑optic setups.
- AAV production/purification infrastructure and molecular biology facilities via the Nyberg Lab and SciLifeLab.
- On‑the‑job training in scientific and technical skills, plus mentoring in writing papers and grant applications, presenting data (talks and posters), supervising students and coordinating collaborative projects.

You will also be part of the broader KI Neuroscience and SciLifeLab communities, with opportunities to attend seminars, workshops, and courses in research leadership, ethics, and data management. As a postdoc in this project, you will be part of KIRI, the Karolinska Institutet Research Incubator, a unique initiative at KI to build a community for interdisciplinary research and breakthrough discoveries. You will have access to two PIs that you can meet and interact with to facilitate the research process and increase the synergetic effects. You will also have the opportunity to meet other KIRI postdocs, present your work at scientific events, and take part in KIRI activities. Read more about KIRI here: https://ki.se/en/research/research-areas-centres-and-networks/research-networks-at-ki/ki-research-incubator-kiri

**Location:** ***Solna***

This is a full‑time postdoctoral position funded by the KIRI‑Fellow postdoc project grant for two years, with the possibility of extension depending on performance and available funding. Employment conditions follow the local agreement for postdoctoral researchers at Karolinska Institutet.

### **Application**

An employment application must contain the following documents in English or Swedish:

- PhD certificate
- A complete resumé, including date of the thesis defence, title of the thesis, previous academic positions, academic title, current position, academic distinctions, and committee work
- Cover letter (1–2 pages) describing your research interests and how they align with the discussed project, your relevant experimental experience, and your motivation for joining the Stagkourakis and Nyberg labs.
- A complete list of publications
- A summary of current work (no more than one page)
- Contact details for at least two references (or reference letters, if available).

The application is to be submitted through the Varbi recruitment system.

## **Want to make a difference? Join us and contribute to better health for all!**

Anställningsform: tidsbegränsad anställning | Anställningens omfattning: heltid | Antal lediga befattningar: 1 | Sysselsättningsgrad: 100% | Ort: Solna | Län: Stockholms län | Land: Sweden | Referensnummer: STÖD 2-1775/2026 | Facklig företrädare: Björn Meister, SACO , Björn Meister, SACO , Alexander Wolthon, ST-OFR , Alexander Wolthon, ST-OFR , | Publicerat: 2026-04-28 | Sista ansökningsdag: 2026-05-19