Circular RNA: From non-coding regulators to functional protein encoders

Abstract

Circular RNAs (circRNAs), a distinct class of non-coding RNAs characterized by a covalently closed circular structure, have gained prominence as a promising research field due to their unique biological properties and functional roles relative to linear RNAs. This review summarizes recent progress in circRNA research, emphasizing fundamental mechanisms and translational potential. We first outline the discovery, biological features, synthesis, and purification of circRNAs. Next, their delivery systems, biological functions, and applications are reviewed. Finally, we discuss challenges and future prospects for clinical translation, with a focus on advancing precision medicine, gene therapy, and personalized vaccines. This review uniquely integrates recent advances in circRNA biology with their translational applications, offering a comprehensive perspective from molecular mechanisms to clinical potential.

Keywords

Circular RNA / Structural features / Biological functions / Gene therapy / Delivery strategies

CRediT authorship contribution statement

Xinwei Zhang: Writing - original draft, Conceptualization. Hongyan Wu: Writing - original draft, Validation, Conceptualization. Xuechuan Hong: Writing - review & editing, Supervision, Funding acquisition, Conceptualization. Yuling Xiao: Writing - review & editing, Project administration, Funding acquisition, Conceptualization. Xiaodong Zeng: Writing - review & editing, Project administration, Methodology, Conceptualization.

Ethics approval

Not applicable.

Declaration of generative AI in scientific writing

During the preparation of this work the author(s) used ChatGPT in order to assist with language editing and refinement of sentence structure. After using this tool/service, the author(s) reviewed and edited the content as needed and take(s) full responsibility for the content of the publication.

Funding

The work was supported by the National Key R&D Program of China (2023YFC3605500), National Natural Science Foundation of China (22477129, 82273796, 82372005, and 82171986), Taishan Scholar Project of Shandong Province (TSQN202306320), Special Supporting Funds for Leading Talents at or above the Provincial Level in Yantai, Natural Science Foundation of Shandong Province (ZR2023MB085, ZR2024QH253), Shandong Laboratory Program (SYS202205).

Data availability

Not applicable.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgements

Not applicable.

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