Figure 1.Schematic representation of rodent IGF-1 gene. The
rodent IGF-1 gene contains six exons (colored boxes), separated by five
introns (black lines). Both exons 1 and 2 contain multiple transcription
start sites (horizontal arrows). Translation initiation codons (AUG) are
located at exons 1, 2 and 3 (vertical arrows). Exons 1, 2 and 3 code for
the signal peptide of precursor IGF-1 (red boxes). Exons 5 and 6 each
encode distinct portions of the E-peptides (green boxes).
