Abstract: DNA encoding two forms of PDGF A-chain polypeptide, the construction of expression vectors for expressing such DNA in yeast and mammalian cells, and the expression of such DNA in yeast and mammalian cells to produce active PDGF A-chain homodimer and active PDGF A-chain/B-chain heterodimer are disclosed.

Abstract: Purified protein known as platelet TGF-.beta.1-BP (transforming growth factor-.beta.1-binding protein) is described. The protein is useful for purposes such as the production of antisera which are useful in identifying complexes containing the binding protein, as well as in formation of labeled probes. Also described are purified DNA which expresses the protein, as well as messenger RNA translated into the protein. The protein contains 16 epidermal growth factors (EGF) like repeats, and 3 repeats not found in other proteins. The DNA for the protein is found to contain consensus sequences for hydroxylation of asparagine/aspartic acid residues, and, in the purified protein beta hydroxylated asparagine residues were found.