Internship: Squeezing cell-derived vesicles: Correlating presence/absence of cytoskeleton with GPMV mechanical properties
As an intern/Master student in the Physics of Cellular Interactions group headed by Dr. Kristina Ganzinger, you will investigate how the mechanical stability of cell-derived vesicles is affected by the presence or absence of an actin cytoskeleton. These vesicles represent a valuable experimental platform as they approximate the composition of cell membranes and can be used in cases when bottom-up reconstitution of model membranes is not feasible. Building on previous experience in the PCI group, you will explore different chemical vesiculation protocols to produce Giant Plasma Membrane Vesicles (GPMVs) and use confocal fluorescence microscopy to comprehensively test for the presence of an actin cytoskeleton in GPMVs formed by various vesiculation agents. You will then use microfluidic traps to cross-compare the deformability of GPMVs, with fully synthetic vesicles serving as a reference. Finally, this will also allow you to explore different approaches to decrease the mechanical resilience of GPMVs, which can inform strategies to create GPMV-derived supported lipid bilayers.
More about the project
Cell membranes are distinguished by their dual functionality: they are the barrier separating the interior of cells from their environment, yet they simultaneously serve as the main interface through which cells exchange matter and signals with their surroundings. GPMVs have been established as model systems to investigate properties of cellular membranes. Whereas GPMV lipid and protein content and orientation in the membrane have been investigated to some degree, the mechanical properties of these vesicles remain mostly unexplored. GPMVs could potentially be used to form a continuous native-like supported lipid bilayer (nSLB) to serve as an experimental platform for single-molecule, high-resolution studies of cell-cell interaction. However, unlike synthetic liposomes, which burst spontaneously upon contact with glass surfaces to form bilayer patches, GPMVs require additional perturbation strategies (e.g. acoustic pressure or creating an air-water interface to increase the membrane tension ), with variable success rates. This is especially interesting since GPMVs derived through certain chemical vesiculation methods are reported to be missing an underlying actin cortex that would stabilize the membrane structures. Importantly, this has not been conclusively demonstrated for all chemical vesiculation agents, and thus specific vesiculation protocols might result in vesicles that are more amenable to nSLB generation.
- Ganzinger, K.A. et al. Angew. Chem. Int. Ed. 2020
- Sezgin, E. et al. Membranes2020
- Chiang, P.-C. et al. Sci Rep2017
About the group
Our group focuses specifically on processes that are critical to communication in the immune system. We address these questions mainly by reconstituting signaling processes in model-membrane systems, developing novel experimental platforms to study immune cell–target cell contacts, and combining them with tools from single-molecule biophysics and microfabrication.
You have a Bachelor’s degree in physics, chemistry or biology and will participate in a Master study during the entire internship period. The internship must be a mandatory part of your curriculum. You have a nationality of an EU member state and/or you are a student at a Netherlands University. Please note: As of January 2021 the UK is no longer an EU member state.
Terms of employment
At the start of the traineeship your trainee plan will be set out, in consultation with your AMOLF supervisor.
Dr. Nebojša Jukić
Postdoctoral Researcher (Physics of Cellular Interactions)
Phone: +31 (0)20-754 7100
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– List of followed courses plus grades.
Applications will be evaluated on a rolling basis and as soon as an excellent match is made, the position will be filled.
Online screening may be part of the selection.
AMOLF is highly committed to an inclusive and diverse work environment. Hence, we greatly encourage candidates from any personal background and perspective to apply.
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