Extended Data Fig. 8: Fabrication of physiological stiffness gradient gels.
From: Collective durotaxis along a self-generated stiffness gradient in vivo
a, Apparent elasticity measurements of shallow (physiological) stiffness gradient gels and uniform stiffness gels. b, Gradient of stiffness from in vivo embryo measurements and ex vivo polyacrylamide gels. c–d, Immunostaining of fibronectin and fluorescent microspheres in gel. Images represent soft and stiff sides of the same gel exhibiting a stiffness gradient, in either top view (c) or side view (d). Scale bar is 100 μm (c, d). e–f, Quantification of fibronectin thickness (e) and mean fluorescence (f). g, Tactic index of clusters seeded on different regions of physiological gradient gels. h–j, Immunostaining of Rac-GTP of clusters on a stiffness gradient or uniformly high stiffness (h), quantification of total Rac-GTP (i) and Rac-GTP polarity (j) on different portions of the gradient gel. Scale bar is 20 μm (h). Thick bars (a, b, e-g, i, j) represent mean; error bars (a, b, e-g, i, j) represent s.d.; unpaired two-tailed t-test (b, e), two-tailed Mann-Whitney U test (f), Dunn’s test (g, i, j); n = 8 (a), 30 (e), 20 (f), 28 (g, 0.6, 1.4), 25 (g, 1), 33 (g, 1.8) gels, 15 (b) clusters and embryos, 29 (i, j) clusters. Statistics and reproducibility are in the source data and Methods
