Synergistic roles of scleraxis and Smads in the regulation of collagen 1α2 gene expression

► Scleraxis regulates collagen 1α2 gene expression in cardiac fibroblasts. ► Scleraxis interacts with E box sites in the human proximal collagen 1α2 promoter. ► Collagen 1α2 expression is synergistically regulated by scleraxis and Smad3. ► A dominant negative scleraxis mutant blocks collagen gene expression by TGF-β1.