Signs of stress on soft surfaces : A commentary on: Cui, Y., F.M. Hameed, B. Yang, K. Lee, C.Q. Pan, S. Park, and M. Sheetz. 2015. Cyclic stretching of soft substrates induces spreading and growth. Nat Commun. 6:6333.

Cells experience mechanical stimuli during growth and differentiation and transduce these stimuli into biochemical signals that in turn regulate cell responses to the imposed forces. Reduced spreading and impaired stress fiber formation are indicators of the mechano-response to growth on soft elastic culture substrates. However, Cui and coworkers demonstrate that cell spreading and stress fiber formation on soft substrates is possible if simultaneous cyclic stretching compensates for the lack of substrate stiffness-induced cell stress. The stress(ed) response is dependent on cyclic stretch amplitude and frequency and, at least in part, mediated by myocardin related transcription factor A (MRTF-A) and Yes-associated protein (YAP). The study thus provides novel insight into the mechanisms of cell mechanosensing and how materials can be designed to mimic mechanical conditions of body tissues.