Two insulin-like growth factor I messenger RNAs are expressed in human liver.

AUTOR(ES)

Rotwein, P

RESUMO

Through use of a synthetic oligonucleotide probe, human insulin-like growth factor I (IGF-I) cDNA clones were isolated from a liver library. Two types of cDNAs were defined by restriction enzyme analysis and DNA sequencing. Both encode IGF-I precursors of either 195 or 153 amino acids. The two predicted protein precursors are identical from their amino terminus to a lysine residue 16 codons beyond the IGF-I sequence, and then they diverge. Both cDNAs predict additional unique carboxyl-terminal extension peptides. Since there is only one IGF-I gene in the human genome, the finding of two different cDNAs suggests that alternative RNA processing plays a role in IGF-I gene expression. The functions of the different extension peptides remain to be elucidated.

Documentos Relacionados

• Insulin-like growth factor I binding in hepatocytes from human liver, human hepatoma, and normal, regenerating, and fetal rat liver.
• Isolation of the human insulin-like growth factor genes: insulin-like growth factor II and insulin genes are contiguous.
• The Role of Liver-Derived Insulin-Like Growth Factor-I
• Genes encoding receptors for insulin and insulin-like growth factor I are expressed in Xenopus oocytes and embryos.
• Bioactive Insulin-Like Growth Factor-I in Obesity