Rac GTPase signaling in mechanotransduction during embryonic morphogenesis

How cells sense and respond to mechanical forces is attracting considerable attention. We recently demonstrated that mechanical tension originating from one tissue strongly influences the differentiation and morphogenesis of another tissue during C. elegans embryogenesis (Nature 471:99-103). Specifically, we found that the repeated contractions of muscle cells stimulate a signaling cascade involving the Rac GTPase within the epidermis. This pathway ultimately leads to strengthen hemidesmosome-like junctions and promote embryonic morphogenesis. Our work provides further evidence that mechanical inputs impact on development, much like inputs involving growth factors and morphogens. After briefly outlining the pioneering work that inspired us, I will present the mechanotransduction process underlying the response to tension and the key experiments supporting our conclusions.