Somatomedin-C shares the carboxy-terminal antigenic determinants with insulin-like growth factor-I.
Insulin-like growth factor I is a human plasma peptide with strong homology to human proinsulin. Many lines of evidence suggest that somatomedin-C and insulin-like growth factor I are identical molecules. However, no structural data regarding the carboxy-terminal end of somatomedin-C has yet been produced. We report a region-specific immunoassay directed against the carboxy-terminal end of insulin-like growth factor I. Somatomedin-C and insulin-like growth factor I are indistinguishable in this region-specific immunoassay. Insulin-like activity II and multiplication stimulating activity show partial cross reaction in this immunoassay. This study provides the first evidence about the carboxy-terminal portion of somatomedin-C and re-emphasizes that somatomedin-C and insulin-like growth factor I should be considered identical molecules.
D055598:Chemical Phenomena; D002621:Chemistry; D000939:Epitopes; D006801:Humans; D007328:Insulin / Q000276:immunology*; D007334:Insulin-Like Growth Factor I; D010455:Peptides / Q000276:immunology*; D011869:Radioligand Assay; D013002:Somatomedins / Q000276:immunology*
D000939:Epitopes; D007328:Insulin; D010455:Peptides; D013002:Somatomedins; D007334:Insulin-Like Growth Factor I