See the force: Imaging cellular forces with molecular force sensors

In a living tissue, cells are subjected to many mechanical cues that are known to play a crucial role in their development. The cells can sense the global and local forces imposed by their environment and induce a variety of responses that directly affect processes such as cell division, differentiation and polarization. That is why changes in cell mechanics are a good indicator of changes in cell physiology, and, for instance, of the progression of a disease. Therefore, being able to measure forces in vivo and at the molecular scale is of great interest in order to understand the mechanical aspect of biological processes within cells. In this project we will tackle this challenge by using molecular mechanochromic force sensors. Those sensors are based on biocompatible conjugated polymers that respond instantaneously to applied stresses by changing their conformation and consequently their fluorescent spectroscopic properties. Recording the spectroscopic responses of those sensors provides with a direct measurement of the applied stresses, which will allow us to quantify and map for the first time the spatio-temporal heterogeneity of mechanical forces, with high resolution and at the scale of the living cell.

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In this project you will:

  • synthesize the sensor by making the appropriate fluorescent conjugated polymer
  • study the optical response of the sensor upon conformational changes/applied stress
  • implement this new sensor in plant cells
  • map the local forces generated in vivo using spectral imaging

This project is a combination of synthetic chemistry, physics and biology.

For deeper insight into the subject:

[1] Hande E Cingil, Emre B Boz, Junyou Wang, Martien A Cohen Stuart, and Joris Sprakel. Probing Nanoscale Coassembly with Dual Mechanochromic Sensors. Advanced Functional Materials, 2016

[2] Ties van de Laar, Hent Schuurman, Pieter van der Scheer, Jan Maarten van Doorn, Jasper van der Gucht, and Joris Sprakel. Light from within: Sensing Weak Strains and FemtoNewton Forces in Single Molecules. Chem 4: 1-16, 2018