circular RNA

biochemistry

Also known as: circRNA

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The Information Architects of Encyclopaedia Britannica

Last updated

July 22, 2026

Quick Summary

Circular RNA (circRNA) is a unique type of RNA where the 5′ and 3′ ends are joined, forming a loop. Unlike linear RNA molecules, circRNAs are generated from protein-encoding genes. Some circRNAs can function as templates for protein synthesis, similar to messenger RNA (mRNA).1

Additionally, circRNAs can act as "sponges" by binding to microRNAs (miRNAs), thereby preventing miRNAs from interacting with their intended targets. They also play a role in regulating the transcription and alternative splicing of the genes from which they originate.1

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Circular RNA (circRNA) is unique from other RNA types because its 5′ and 3′ ends are bonded together, creating a loop. The circRNAs are generated from many protein-encoding genes, and some can serve as templates for protein synthesis, similar to mRNA. They can also bind…
Read More
Circular RNA (circRNA) is unique from other RNA types because its 5′ and 3′ ends are bonded together, creating a loop. The circRNAs are generated from many protein-encoding genes, and some can serve as templates for protein synthesis, similar to mRNA. They can also bind…
Read More