title: Circular intronic long noncoding RNAs.
abstract: We describe the identification and characterization of circular intronic long noncoding RNAs in human cells, which accumulate owing to a failure in debranching. The formation of such circular intronic RNAs (ciRNAs) can be recapitulated using expression vectors, and their processing depends on a consensus motif containing a 7 nt GU-rich element near the 5' splice site and an 11 nt C-rich element close to the branchpoint site. In addition, we show that ciRNAs are abundant in the nucleus and have little enrichment for microRNA target sites. Importantly, knockdown of ciRNAs led to the reduced expression of their parent genes. One abundant such RNA, ci-ankrd52, largely accumulates to its sites of transcription, associates with elongation Pol II machinery, and acts as a positive regulator of Pol II transcription. This study thus suggests a cis-regulatory role of noncoding intronic transcripts on their parent coding genes.
authors.affiliation: State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xiao-Ou
authors.initials: XO
authors.lastname: Zhang
authors.forename: Tian
authors.initials: T
authors.lastname: Chen
authors.forename: Jian-Feng
authors.initials: JF
authors.lastname: Xiang
authors.forename: Qing-Fei
authors.initials: QF
authors.lastname: Yin
authors.forename: Yu-Hang
authors.initials: YH
authors.lastname: Xing
authors.forename: Shanshan
authors.initials: S
authors.lastname: Zhu
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.forename: Ling-Ling
authors.initials: LL
authors.lastname: Chen
mesh_terms: D004257:DNA Polymerase II / Q000235:genetics*; D055785:Gene Knockdown Techniques; D006801:Humans; D007438:Introns / Q000235:genetics; D035683:MicroRNAs / Q000235:genetics; D012319:RNA Polymerase II / Q000235:genetics*; D022821:RNA Splice Sites; D062085:RNA, Long Noncoding / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D035683:MicroRNAs; D022821:RNA Splice Sites; D062085:RNA, Long Noncoding; D012319:RNA Polymerase II; D004257:DNA Polymerase II