The TGfB1 gene is mapped to human chromosome 19q13.2 and codes for a 25 kDa peptide. TGf-AY1 polypeptide is produced as a precursor with hydrophobic signal sequence pro-region and mature peptide. Cleavage of the precursor at tetrabasic cleavage site results in monomers of carboxy-terminal 112 amino acids. The biologically active form of Tgfb1 exists as a disulphide-linked homodimer.
