Controlling cell differentiation precisely in space and time is a challenge in stem cell research with obvious application in regenerative medicine. Whereas decades of research have identified the molecular pathways governing cell fate specification, how the activity of these pathways is modulated spatiotemporally to properly pattern the developing embryo remains elusive. The mechanical environment, reported to influence stem cell differentiation in vitro, has recently emerged as a critical cue guiding cell differentiation. However, it is still unclear how mechanical forces play such a role in vivo, in developing embryos. Taking advantage of avian embryos’ amenability to live imaging and their great accessibility, our laboratory has developed novel transgenic quail lines, live imaging approaches, and controlled mechanical perturbations to interrogate the role of mechanical forces in cell fate specification. We are now able to impose controlled forces in live embryos, monitor the induced deformation (compression, stretch, or shear) in real-time and test the effect of these deformations on selected candidate genes. With the ambition to probe the effect of mechanical perturbation at the genome scale, we recently adapted the spatial transcriptomics Visium technology (10x Genomics) to spatially correlate local tissue deformation in entire embryos (5mm diameter, 30μm thick embryo, 100k cells, not cryosections) with transcriptomic changes. Although the results validate the feasibility of our approach, this technique yields only a tissue-scale resolution due to the low resolution of the bar-coding of the Visium chip. In summary, this project aims to characterize the role of mechanics in embryonic stem cell differentiation by linking cells’ transcriptome to their mechanical state in vivo, in control and perturbed embryos, and at a single-cell level, which to the best of our knowledge has never been performed before.
Related team publications: