Molecular evolution methods, in which functional peptides are searched for from random amino acid peptides or introducing random amino acid mutations into a protein, has become an indispensable basic technology for drug development and physiological function analysis. The simplest way to introduce such mutations into the amino acid sequences of peptide backbones is to introduce random mutations into genes and express peptides or proteins in vitro or in cells. The technology of mutagenesis has a long history of more than 30 years, during which many techniques have been developed and put into practical use. However, high-throughput screening of peptides and proteins with random mutations must be designed for specific purposes.

In our laboratory, we have established an original screening technique to select target proteins by converting a mutant gene library into a retrovirus library. Using this technology, we have applied it to the comprehensive analysis of mitochondrial proteins and proteins transported into intracellular organelles, as well as to the identification of target peptide sequences for localization in the mitochondrial intermembrane space. This technology is expected to be applied in various ways as an basic technology for screening functional peptides and proteins.

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