Differential regulation by glucocorticoids of mouse pro alpha 2(I) and pro alpha 1(III) DNA-binding proteins

Multiple procollagen-specific DNA-binding proteins were identified for the alpha 2(I) and the alpha 1(III) procollagen promotor containing gene fragments. The proteins are gene-specific, differing in their relative molecular weights and relative binding specificities. A major finding was the increased DNA-binding with specificity for the procollagen promoter containing DNAs by several nonhistone nuclear proteins in mouse embryo fibroblasts treated with dexamethasone. The previously reported coordinate decrease of type I and type III procollagens by glucocorticoids may involve differential regulation by glucocorticoids of procollagen gene specific DNA-binding proteins.