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Efficient viral delivery system for unnatural amino acid mutagenesis in mammalian cells.

ABSTRACT: Here we report the development of a baculovirus-based delivery system that enables the efficient incorporation of unnatural amino acids into proteins in mammalian cells. We have exploited the large cargo-capacity (>30 kb) and stability of the double-stranded DNA genome of baculovirus to deliver to a variety of cell types all of the components required to genetically incorporate novel amino acids. These include the engineered tRNA/aminoacyl-tRNA synthetase pair and the nonsense mutant of the target gene. Mammalian cell transduction efficiency of baculovirus was significantly improved by incorporating genetic elements from mammalian viruses. Two polyspecific tRNA/aminoacyl-tRNA synthetase pairs were inserted into this expression system, enabling the site-specific incorporation of a variety of unnatural amino acids with novel chemical and biological properties into proteins.

SUBMITTER: Chatterjee A

PROVIDER: S-EPMC3718144 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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Efficient viral delivery system for unnatural amino acid mutagenesis in mammalian cells.

Chatterjee Abhishek A Xiao Han H Bollong Michael M Ai Hui-Wang HW Schultz Peter G PG

Proceedings of the National Academy of Sciences of the United States of America 20130701 29

Here we report the development of a baculovirus-based delivery system that enables the efficient incorporation of unnatural amino acids into proteins in mammalian cells. We have exploited the large cargo-capacity (>30 kb) and stability of the double-stranded DNA genome of baculovirus to deliver to a variety of cell types all of the components required to genetically incorporate novel amino acids. These include the engineered tRNA/aminoacyl-tRNA synthetase pair and the nonsense mutant of the targ ...[more]

PMID: 23818609

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