Focus issue: TGF-β and the mesenchymal transition in physiology and disease

Abstract

The ability of cells to alter their phenotypic and morphological characteristics, known as cellular plasticity, is critical in normal embryonic development and adult tissue repair and contributes to the progression of diseases like organ fi brosis and cancer. Signaling mediated by the transforming growth factor β (TGF-β) superfamily of extracellular protein ligands is one pathway that is integral to these processes. Content published in Science Signaling highlights the roles and complexities of TGF-β signaling in physiology and disease.