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Genetic Alphabet Expansion of Nucleic Acids

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Handbook of Chemical Biology of Nucleic Acids

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Abstract

Genetic alphabet expansion is a novel concept to expand the letters of DNA, RNA, and proteins in the central dogma. This concept allows increases in the genetic information complexity and the functionalities of these biomolecules, by introducing additional components via biological systems in the programmed manner encoded on DNA with additional letters. To apply this concept to current biotechnology systems, the development of artificial extra base pairs (unnatural base pairs, UBPs) that function in replication, transcription, and/or translation is a prerequisite milestone. Several UBPs have recently been developed and applied to qPCR methods, DNA aptamer generation, site-specific labeling of RNAs, semisynthetic organism (SSO) creation, and protein synthesis involving non-standard amino acids. The introduction of hydrophobic components significantly increases the affinity of DNA aptamers to target proteins. The SSO systems with six-letter DNA/RNA produce novel functional proteins containing non-standard amino acids. Here, the development of UBPs and their applications to qPCR, DNA aptamers, and RNA modifications are discussed by focusing on UBP studies in nucleic acids.

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Authors and Affiliations

  1. Institute of Bioengineering and Bioimaging (IBB), A*STAR and Xenolis Pte. Ltd., Singapore, Singapore

    Michiko Kimoto & Ichiro Hirao

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  1. Michiko Kimoto
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  2. Ichiro Hirao
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Correspondence to Ichiro Hirao .

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  1. Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, Kobe, Japan

    Naoki Sugimoto

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  1. University of Utah, Salt Lake City, USA

    Cynthia Burrows

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Kimoto, M., Hirao, I. (2023). Genetic Alphabet Expansion of Nucleic Acids. In: Sugimoto, N. (eds) Handbook of Chemical Biology of Nucleic Acids. Springer, Singapore. https://doi.org/10.1007/978-981-16-1313-5_48-1

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  • DOI: https://doi.org/10.1007/978-981-16-1313-5_48-1

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