Receptors for insulin-like growth factors I and II

摘要: The somatomedins (SMs) comprise a family of growth hormone (GH)-dependent, insulin-like peptides with metabolic and mitogenic actions in wide variety cell lines (Phillips Vassilopoulou-Sellin 1980). While their precise role the regulation cellular replication remains uncertain, growing body data supports hypothesis that these mediate many anabolic GH 1980; Schoenle et al. 1982). Two human SMs, factors (IGF) I II, have been purified, sequenced, found to 62% identity amino acid positions (Rinderknecht Humbel 1978a, b). Furthermore, striking structural homology proinsulin. sequences cDNAs encoding for pre-proIGF-I -II elucidated respective 130 180 precursors predicted (Jansen 1983; Bell 1984; Dull 1984). IGF-II has mapped short arm chromosome 11, tightly linked both insulin gene c-Ha-ras 1 proto-oncogene (Brissenden Tricoli IGF-I maps 12, which is evolutionarily related 11 carries c-Ki-ras2 proto-oncogene. These homologies suggest evolutionary conservation common critical peptide skeleton raise important questions concerning each how cells peptide’s biological activities. As would suggest, weak effects, while shares growth-promoting IGFs (Rosenfeld Hintz 1986).