Professor Guillaume Charras leads a research group at the London Centre for Nanotechnology. Their overall goal is to understand fundamental mechanical properties of cells and tissues. They are particularly interested in the interplay between signalling and cell mechanics and how mechanical changes govern cellular and embryonic morphogenesis.
The group have used AFM from JPK Instruments for over a decade. Indeed, AFM offers a quantitative method for estimating mechanical properties. While originally restricted cellular mechanics, the expanded z-range of JPK's CellHesion® 200 allows studies on cultured and embryonic tissues. The recent purchase of a NanoWizard® 4 BioScience AFM system will allow the group to image changes in the organization of the submembranous actin cortex (the main determinant of cell shape) as the cell undergoes mitosis. This will complement other microscopies such as scanning electron microscopy for the cortex organization at the scale of single actin filaments, confocal microscopy for imaging localization of proteins during morphogenesis at high frame rate, and optogenetics to manipulate cell signalling.
When asked about why he particularly likes using the instrumentation from JPK, Professor Charras said, "I find their systems reliable and very user-friendly. The large z range is vital to our work and the possibility to combine this with multi-position imaging allows us to extract the maximum amount of data from each experiment. We have illustrated this in a paper when we used the CellHesion® 200. This has an extra long z piezo range of 100 μm that enabled us to collect force-indentation data over a large indentation range while ensuring there was separation of the tip from the sample during retraction.1 Furthermore, the long z-range has now made it possible to monitor changes in mechanical properties in living frog embryos2. With the arrival of our latest NanoWizard® AFM, we are optimistic of more ground-breaking publications in the coming months."
For more details about JPK's AFM systems and their applications for the materials, life & nano sciences, please contact JPK on +49 30726243 500. Alternatively, please visit the web site: www.jpk.com or see more on Facebook: www.jpk.com/facebook and on You Tube: http://www.youtube.com/jpkinstruments.
For a high resolution copy of the image, either right click to download or contact Jezz Leckenby at Talking Science.
References
1 Formulation of adherens junctions leads to the emergence of a tissue-level tension in epithelial monolayers, A R Harris, A Daeden and G T Charras, Journal of Cell Science (2014) 127, 2507–2517 doi:10.1242/jcs.142349
2 Tissue stiffening coordinates morphogenesis by triggering collective cell migration in vivo. E H Barriga, K Franze, G T Charras, R Mayor. Nature. 2018 Feb 14. doi: 10.1038/nature25742