title: Complete characterization of the human IGF-I nucleotide sequence isolated from a newly constructed adult liver cDNA library.
abstract: A full-size cDNA sequence coding for insulin-like growth factor I (IGF-I) was isolated from a human liver library. For the construction of this bank, a new method was developed which anneals dG-tailed cDNA with a synthetic adaptor 5'-AATTCCCCCCCCCCC-3' followed by ligation into the EcoRI site of a lambda immunity-insertion vector. Based on the sequence analysis of the complete IGF-I messenger we concluded that the protein is synthesized as a precursor containing a signal peptide of 22 or 25 amino acid residues. In addition, the sequence extended in the 3'-direction and showed the presence of multiple polyadenylation sites in the IGF-I message.
mesh_terms: D000595:Amino Acid Sequence; D010582:Bacteriophage lambda / Q000235:genetics; D001483:Base Sequence; D003001:Cloning, Molecular / Q000379:methods*; D004247:DNA / Q000032:analysis; D004274:DNA, Recombinant / Q000032:analysis; D005822:Genetic Vectors; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000235:genetics*; D008099:Liver / Q000032:analysis; D013002:Somatomedins / Q000235:genetics*
chemical_list: D004274:DNA, Recombinant; D013002:Somatomedins; D007334:Insulin-Like Growth Factor I; D004247:DNA