The influence of the four bBMPs on C2C12 cell adhesion and spreading, as mechanotransduction parameters, and pSMAD1,5,9, pSMAD2 and ALP activity, as differentiation parameters, is represented for (a) soft and (b) rigid films. Moreover, the role of the BMP receptors type I, type II and the three β chain integrins analyzed, on the mechanotransduction and differentiation parameters aforementioned, are depicted for each type of receptor: (c) type I BMPR, (d) type II BMPR, and (e) β chain integrins. Since no relevant stiffness-dependent differences were generally observed for the receptors, no specific detailed distinction between soft and rigid films is represented.