| pubmed-article:2996761 | pubmed:abstractText | Transforming growth factors (TGFs) are differentially expressed in the mouse during neonatal development. Highest levels are seen early at Day 7, and lower levels, at Day 13. Both small- and large-molecular-weight forms of TGF are found; they share many biochemical properties with rat TGF-alpha, including a similar high-pressure liquid chromatography elution profile. Although the embryo-derived activities compete with epidermal growth factor for binding to epidermal growth factor membrane receptors, they are immunologically distinct from epidermal growth factor. These embryonic polypeptides, however, do cross-react in a competitive radioimmunoassay developed using a synthetic peptide corresponding to the carboxy-17 amino acids of rat TGF-alpha as the immunogen. The highly conserved TGF-alpha family of peptides produced by some tumor cells may therefore represent derepressed forms of these embryonic growth factors. A functional role in neonatal development is proposed. | lld:pubmed |
