UMMS Affiliation

Program in Bioinformatics and Integrative Biology; RNA Therapeutics Institute

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Biochemical Phenomena, Metabolism, and Nutrition | Biochemistry, Biophysics, and Structural Biology | Bioinformatics | Genetics and Genomics | Nucleic Acids, Nucleotides, and Nucleosides


Circular RNAs (circRNAs) are covalently closed RNAs derived from back-splicing of genes across eukaryotes. Through alternative back-splicing (ABS), a single gene produces multiple circRNAs sharing the same back-splice site. Although many ABS events have recently been discovered, to what extent ABS involves in circRNA biogenesis and how it is regulated in different human tissues still remain elusive. Here, we reported an in-depth analysis of ABS events in 90 human tissue transcriptomes. We observed that ABS occurred for about 84% circRNAs. Interestingly, alternative 5' back-splicing occurs more prevalently than alternative 3' back-splicing, and both of them are tissue-specific, especially enriched in brain tissues. In addition, the patterns of ABS events in different brain regions are similar to each other and are more complex than the patterns in non-brain tissues. Finally, the intron length and abundance of Alu elements positively correlated with ABS event complexity, and the predominant circRNAs had longer flanking introns and more Alu elements than other circRNAs in the same ABS event. Together, our results represent a resource for circRNA research-we expanded the repertoire of ABS events of circRNAs in human tissue transcriptomes and provided insights into the complexity of circRNA biogenesis, expression, and regulation.


Circular RNAs, circRNAs

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Copyright The Author(s) 2020. Published by Oxford University Press on behalf of Nucleic Acids Research. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.

DOI of Published Version



Zhang P, Zhang XO, Jiang T, Cai L, Huang X, Liu Q, Li D, Lu A, Liu Y, Xue W, Zhang P, Weng Z. Comprehensive identification of alternative back-splicing in human tissue transcriptomes. Nucleic Acids Res. 2020 Feb 28;48(4):1779-1789. doi: 10.1093/nar/gkaa005. PMID: 31974555; PMCID: PMC7038940. Link to article on publisher's site

Journal/Book/Conference Title

Nucleic acids research

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Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.