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Updated: Jul 20, 2025
08:25
Identification of Circular RNAs using RNA Sequencing
Published on: November 14, 2019
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Exon Junction Complex Mediates the Cap-Independent Translation of Circular RNA.
Hui-Hsuan Lin1,2, Chiu-Yuan Chang2, Yi-Ren Huang2
1Doctoral Program in Tissue Engineering and Regenerative Medicine, National Chung Hsing University, Taichung, Taiwan.
Molecular Cancer Research : MCR
|August 1, 2023
Summary
Splicing enables circular RNAs (circRNAs) to be translated independently of a cap structure, a process mediated by the exon junction complex (EJC). This EJC-dependent translation of circSDHAF2 is crucial for colorectal cancer development.
Area of Science:
- Molecular Biology
- RNA Biology
- Cancer Research
Background:
- Circular RNAs (circRNAs) are increasingly recognized for their potential to act as protein templates.
- The mechanisms controlling cap-independent translation of circRNAs are not well understood.
Purpose of the Study:
- To elucidate the regulatory mechanisms of cap-independent translation in circRNAs.
- To investigate the role of circRNAs in colorectal cancer tumorigenesis.
Main Methods:
- Investigated the role of splicing in circRNA translation using spliceosome inhibitors and mutations.
- Utilized Cas13 technology for exon junction complex (EJC) tethering experiments.
- Quantified circSDHAF2 levels in colorectal cancer tissues and assessed its role in cellular and murine models.
Main Results:
- Splicing was found to promote cap-independent translation of circRNAs by facilitating EJC acquisition.
- EJC tethering reconstituted EJC-dependent circRNA translation, confirming its role.
- Elevated levels of coding circSDHAF2 were observed in colorectal cancer tissues.
- circSDHAF2 was demonstrated to be critical in colorectal cancer cell and murine models.
Conclusions:
- The exon junction complex (EJC) mediates cap-independent translation of circRNAs.
- EJC-dependent translation of circSDHAF2 plays a significant role in colorectal cancer development.
- circSDHAF2 is a potential therapeutic target in colorectal cancer.
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