FIGURE 2.

Rigidity sensing of FN matrix is RPTPα dependent. (A) Western blot showing the expression of RPTPα in control (CT) and knockdown (A1 and A2) cells. (B) Mechanical properties of polyacrylamide substrate. The Young's modulus (N/m²) of polyacrylamide gels with a range of bis-acrylamide (0.03%, 0.08%, 0.2%, and 0.4%) to acrylamide (8%) was measured as described by Pelham et al. (2). (C) The spread areas of RPTPα^+/+, RPTPα^−/−, and RPTPα knockdown (A2) cells on polyacrylamide substrates of different rigidities. Results shown are the mean ± SD of at least 50 cells.