optimization and construction of human insulin-like growth factor 1 gene related to human health

Background and aims: laron syndrome is a disease that treated by insulin-like growth factor 1 (igf-1). this protein is a single chain and has three disulfide bonds. people with laron syndrome have low rates of cancer and diabetes, although they appear to be at increased risk of casual death due to their stature. igf-1 is synthesized by many tissues and is secreted from liver as an endocrine hormone which is transmitted to other tissues. igf-1 is responsible for cell differentiation, transformation, suppression of apoptosis, cell cycle progression, cell proliferation and differentiation. expression system, the igf-1 gene, codon adaptation index (cai) and gc contents are very critical for the large scale production of this protein. current study was aimed to optimization and construction of human igf-1 gene in e. coli dh5α. methods: we used dna2 and protparam softwares for designing the best form to produce igf-1. first, the coding sequence was verified and then synthesized. for confirmation of the puc18-igf-1, sequencing test was carried out using m13 reverse primer. finally it was inserted into the cloning site of puc18. results: after coding optimization, the cai rate was increased from 84 % to 90% and gc content from 55.07 % to 56.62%. the presence of the band near 225bp resulted from enzymatic digestion with 2 restriction enzymes demonstrates the correct cloning of the recombinant vectors in the cloning site of puc18 cloning vector. conclusion: according to software and experimental analysis, the designed sequence probably in the best form could be used for production of recombinant protein.