The physics of cell division studied through synthetic cells

Cells are the smallest autonomous building blocks of our body. Their shape and mechanics are governed by a delicate force balance between the plasma membrane and the cytoskeleton, an elastic scaffold of stiff protein filaments. The cytoskeleton mechanically stabilizes the thin and fragile lipid bilayer membrane but also actively drives changes in membrane shape by exerting pushing and pulling forces. A paradigmatic example of this mechanical interplay is the process of cell division, which is driven by a contractile ring of actin filaments that constricts the membrane mid-cell. The key structural component is a cross-linked network of actin filaments that is tightly anchored to the plasma membrane and constriction is driven by myosin motor molecules that utilize ATP to slide the actin filaments. Most research till now has focused on the question how force generation by the actin cytoskeleton changes membrane shape.

The aim of this project is to ask the reverse question: how does the membrane geometry determine the assembly and constriction of the actin ring? Models suggest that actomyosin ring formation and furrow ingression sensitively depend on the cell geometry and the balance between cortical tension at the cell equator and the poles. Some models predict that contractile ring initiation furthermore requires cooperation with lipids and proteins that promote membrane curvature. To experimentally test these ideas, you will reconstitute synthetic cells by encapsulating a minimal machinery required for actin ring assembly inside lipid vesicles and use microfluidic devices, optical tweezers, and curvature-inducing proteins to impose a controlled membrane geometry. To measure the dynamic response of the actin and the membrane, you will make extensive use of confocal fluorescence imaging, FCS, FRAP, and single-molecule imaging. This project is part of a large Dutch research initiative (Basyc) aimed at building an autonomous self-reproducing synthetic cell. Our team’s contribution focuses on the mechanical machinery needed to achieve cell cleavage. Within the team, you will closely collaborate with three PhD students that work on several different aspects of the actin-based cell division machinery.

We offer an inspiring, supportive and collegial environment. The Koenderink lab is an experimental biophysics lab studying the physical principles that underlie the self-organization and dynamics of living cells with quantitative physics-based methods. The work addresses both fundamental biological questions on cell and tissue morphogenesis and physics questions on the ‘active soft matter’ properties of living matter. The Koenderink lab is embedded in the TU Delft Department of Bionanoscience, which focuses on the fundamental understanding of biological processes from molecule to cell. The department features an inspiring, international environment with access to state-of-the art facilities for nanofabrication, imaging, molecular/cell biology, biochemistry, and high-performance computing for image processing. Within the department, we closely collaborate with several other groups on the Basyc project.

We seek an outstanding experimental scientist with a strong affinity for research at the interface of physics, biology and chemistry and with relevant research experience in fields such as biophysics, soft matter science, single-molecule techniques, optical microscopy, nanoscience, and/or quantitative cell biology. We are looking for a candidate with a high level of intellectual creativity and genuine interest in fundamental research. You have a hands-on mentality, demonstrated ability to work in a strongly multi-disciplinary environment, and you can easily and effectively communicate with scientists from different disciplines. Women are particularly encouraged to apply, as they typically make up a smaller fraction of the applicant pool. Candidates who want to seek independent funding for their own research agenda are encouraged to discuss possible options. There are many options, which we can explore together, and the Research Funding team of the TU Delft Valorisation centre can offer support.

Successful applicants must

• hold a PhD degree, or approach its completion, in physics, chemistry, (bio)engineering, materials science, nanoscience, or a closely related discipline;
• have excellent written and spoken English skills;
• thrive in an international, multidisciplinary and collaborative environment;
• submit a motivation letter describing why you apply for this position, your research interests, and your fit to the group (no more than 1 A4), a detailed CV with publication list, and recommendation letters from 3 references. 

Fixed-term contract: 2 jaar.

Salary and benefits are in accordance with the Collective Labour Agreement for Dutch Universities. The TU Delft offers a customisable compensation package, a discount on health insurance and sport memberships, and a monthly work costs contribution. Flexible work schedules can be arranged.

For international applicants we offer the Coming to Delft Service and Partner Career Advice to assist you with your relocation. An International Children's Centre offers childcare and there is an international primary school.

Delft University of Technology

Delft University of Technology is built on strong foundations. As creators of the world-famous Dutch waterworks and pioneers in biotech, TU Delft is a top international university combining science, engineering and design. It delivers world class results in education, research and innovation to address challenges in the areas of energy, climate, mobility, health and digital society. For generations, our engineers have proven to be entrepreneurial problem-solvers, both in business and in a social context. At TU Delft we embrace diversity and aim to be as inclusive as possible (see our Code of Conduct). Together, we imagine, invent and create solutions using technology to have a positive impact on a global scale.

Challenge. Change. Impact! 

Faculty Applied Sciences

With more than 1,000 employees, including 135 pioneering principal investigators, as well as a population of about 3,400 passionate students, the Faculty of Applied Sciences is an inspiring scientific ecosystem. Focusing on key enabling technologies, such as quantum- and nanotechnology, photonics, biotechnology, synthetic biology and materials for energy storage and conversion, our faculty aims to provide solutions to important problems of the 21st century. To that end, we train students in broad Bachelor's and specialist Master's programmes with a strong research component. Our scientists conduct ground-breaking fundamental and applied research in the fields of Life and Health Science & Technology, Nanoscience, Chemical Engineering, Radiation Science & Technology, and Engineering Physics. We are also training the next generation of high school teachers and science communicators.

Click here to go to the website of the Faculty of Applied Sciences.