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Updated: May 27, 2025
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An In Vitro Single-Molecule Imaging Assay for the Analysis of Cap-Dependent Translation Kinetics
Published on: September 15, 2020
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Internal cap-initiated translation for efficient protein production from circular mRNA
Kosuke Fukuchi1, Yuko Nakashima1, Naoko Abe2
1Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya, Japan.
Nature Biotechnology
|February 19, 2025
Summary
Two novel circular mRNA designs enhance protein production for RNA therapeutics. These innovations improve translation efficiency and reduce immune response, expanding therapeutic potential.
Area of Science:
- Biochemistry
- Molecular Biology
- RNA Therapeutics
Background:
- Circular mRNA offers therapeutic potential but faces challenges in translation efficiency.
- Existing methods like internal ribosome entry site (IRES) have limitations.
Purpose of the Study:
- To develop molecular designs for enhanced circular mRNA translation.
- To improve the therapeutic applicability of circular mRNA.
Main Methods:
- Covalent attachment of N7-methylguanosine (m7G) cap to circular mRNA (cap-circ mRNA).
- Non-covalent cap attachment via hybridization with a complementary oligonucleotide.
- Incorporation of N1-methylpseudouridine (m1Ψ) modification.
Main Results:
- Cap-circ mRNA demonstrated superior protein production compared to IRES-containing circular mRNA.
- Cap-circ mRNA with m1Ψ modification showed reduced immunostimulatory effects in mice while maintaining high translation.
- Non-covalent cap attachment enhanced circular mRNA translation over 50-fold.
- Circular mRNA designs facilitated rolling circle-type translation and synthesis of reporter proteins.
Conclusions:
- Novel cap attachment strategies significantly boost circular mRNA translation efficiency.
- These designs offer a smaller molecular size and improved therapeutic potential for RNA therapeutics.
- The developed methods facilitate cell-type-selective translation, broadening therapeutic applications.
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