Fig. 4: Full-length talin WT cooperates with kindlin through paxillin to induce stronger cell adhesion in comparison with talin-H.
From: Mechanism of integrin activation by talin and its cooperation with kindlin
a Cell adhesion of talin1/2dKO fibroblasts expressing ypet, ypet-tagged talin head (tlnH), talin WT, or constitutively active talin (tlnM3) on fibronectin- or vitronectin-coated surfaces. WT values were set to 1. Data represent mean ±95% CI. N = 4/3 experiments. Fibronectin: **p = 0.0050, ***p = 0.0007, Vitronectin: *p = 0.0179, **p = 0.0068 (one-way ANOVA followed by Tukey’s multiple-comparison test). b Cell-spreading area of cells expressing tlnH, tlnWT, or tlnM3 seeded on fibronectin after 30 min. Data are presented as mean ±95% CI. N = 4 experiments. ***p < 0.0001. (c/d) Cell adhesion of talin1/2dKO rescued with ypet alone, ypet–tlnH, or ypet–tlnWT in the presence (K2WT) or absence (K2KO) of kindlin-2. Kindlin-2 was knocked out by CRISPR/Cas9, K2WT cells were treated with a nontargeting control guideRNA. (c) Expression levels of ypet, full- length talin, talin head, and kindlin-2 assessed by Western blot. GAPDH served as loading control. d Static adhesion assays of the mentioned cell lines on fibronectin-coated surfaces. Data represent mean ±95% CI. N = 5 independent experiments. *p = 0.0339 (tlnH/K2WT vs tlnWT/K2WT), p = 0.0276 (tlnWT/K2WT vs tlnH/K2KO), p = 0.0199 (tlnWT/K2WT vs tlnWT/K2KO), **p = 0.0072 (one-way ANOVA followed by Tukey’s multiple-comparison test). e Western blots showing expression of mCherry, talin, kindlin-2, and paxillin in K2KO ypet–talinWT-expressing cells retrovirally transduced with expression constructs carrying mCherry or mCherry-tagged wild-type (K2WT) or paxillin-binding defective (K2GLKE) kindlin-2 and subsequently treated either with negative control (NC) or paxillin-targeting (pxn_s04) siRNA. GAPDH served as loading control. Representative blots from one out of four experiments are shown. f Static adhesion assay of transduced cells with or without paxillin-targeting siRNA treatment. Data represent mean ±95% CI. N = 7 independent experiments. **p = 0.0052, ***p = 0.0004 (K2WT/NC vs K2GLKE/NC), p = 0.0001 (K2WT/NC vs K2GLKE/pxn_s04) (one-way ANOVA followed by Tukey’s multiple-comparison test). Uncropped images (c, e) and raw data (a, b, d, f) are provided as a Data Source file.
