Effects of codon optimization on coagulation factor IX translation and structure: Implications for protein and gene therapies

作者：Aikaterini Alexaki, Gaya K. Hettiarachchi, John C. Athey, Upendra Katneni, Vijaya Lakshmi Simhadri, Nobuko Hamasaki‐Katagiri, Puja Nanavaty, Brian Lin, Kazuyo Takeda, Darón I. Freedberg, Dougald M. Monroe, Joseph R. McGill, Robert Peters, Jacob M. Kames, David D. Holcomb, Ryan Hunt, Zuben E. Sauna, Amy D. Gelinas, Nebojša Janjić, Michael N. DiCuccio, Haim Bar, Anton A. Komar, Chava Kimchi‐Sarfaty · 发表于：Scientific Reports · 年份：2019 · DOI：10.1038/s41598-019-51984-2 · 被引用次数：81 · 研究领域：RNA and protein synthesis mechanisms、Monoclonal and Polyclonal Antibodies Research、Viral Infectious Diseases and Gene Expression in Insects

Synonymous codons occur with different frequencies in different organisms, a phenomenon termed codon usage bias. Codon optimization, a common term for a variety of approaches used widely by the biopharmaceutical industry, involves synonymous substitutions to increase protein expression. It had long been presumed that synonymous variants, which, by definition, do not alter the primary amino acid sequence, have no effect on protein structure and function. However, a critical mass of reports suggests that synonymous codon variations may impact protein conformation. To investigate the impact of synonymous codons usage on protein expression and function, we designed an optimized coagulation factor IX (FIX) variant and used multiple methods to compare its properties to the wild-type FIX upon expression in HEK293T cells. We found that the two variants differ in their conformation, even when controlling for the difference in expression levels. Using ribosome profiling, we identified robust changes in the translational kinetics of the two variants and were able to identify a region in the gene that may have a role in altering the conformation of the protein. Our data have direct implications for codon optimization strategies, for production of recombinant proteins and gene therapies.