Interior circular RNA

Xiaoxin Liu, Zhangfeng Hu, Junfei Zhou, Cheng Tian, Guangmei Tian, Miao He, Lifen Gao, Lihong Chen, Tiantian Li, Hai Peng, Weixiong Zhang

Research output: Contribution to journalArticlepeer-review

22 Scopus citations


Formed by back splicing or back fusion of linear RNAs, circular RNAs (circRNAs) constitute a new class of non-coding RNAs of eukaryotes. Recent studies reveal a spliceosome-dependent biogenesis of circRNAs where circRNAs arise at the intron-exon junctions of mRNAs. In this study, using a novel de novo identification method, we show that circRNAs can originate from the interior regions of exons, introns, and intergenic transcripts in human, mouse and rice, which were referred to as interior circRNAs (i-circRNAs). Many i-circRNAs have some remarkable characteristics: multiple i-circRNAs may arise from the same genomic locus; their back fusion points may not be associated with the AG/GT splicing sites, but rather a new pair of motif AC/CT, their back fusion points are adjacent to complementary sequences; and they may circulate on short homologous sequences. We validated several i-circRNAs in HeLa cells by Polymerase Chain Reaction followed by Sanger sequencing. Our results combined showed that i-circRNAs are bona fide circRNAs, indicated novel biogenesis pathways independent of the splicing apparatus, and expanded our understanding of the origin, diversity, and complexity of circRNAs.

Original languageEnglish
Pages (from-to)87-97
Number of pages11
JournalRNA Biology
Issue number1
StatePublished - Jan 2 2020


  • PCR
  • RNA
  • RNA sequencing
  • Sanger sequencing
  • chimeric RNA
  • circular RNA


Dive into the research topics of 'Interior circular RNA'. Together they form a unique fingerprint.

Cite this