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Alu element-containing RNAs maintain nucleolar structure and function.

ABSTRACT: Non-coding RNAs play a key role in organizing the nucleus into functional subcompartments. By combining fluorescence microscopy and RNA deep-sequencing-based analysis, we found that RNA polymerase II transcripts originating from intronic Alu elements (aluRNAs) were enriched in the nucleolus. Antisense-oligo-mediated depletion of aluRNAs or drug-induced inhibition of RNA polymerase II activity disrupted nucleolar structure and impaired RNA polymerase I-dependent transcription of rRNA genes. In contrast, overexpression of a prototypic aluRNA sequence increased both nucleolus size and levels of pre-rRNA, suggesting a functional link between aluRNA, nucleolus integrity and pre-rRNA synthesis. Furthermore, we show that aluRNAs interact with nucleolin and target ectopic genomic loci to the nucleolus. Our study suggests an aluRNA-based mechanism that links RNA polymerase I and II activities and modulates nucleolar structure and rRNA production.

SUBMITTER: Caudron-Herger M

PROVIDER: S-EPMC4682651 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Alu element-containing RNAs maintain nucleolar structure and function.

Caudron-Herger Maïwen M Pankert Teresa T Seiler Jeanette J Németh Attila A Voit Renate R Grummt Ingrid I Rippe Karsten K

The EMBO journal 20151013 22

Non-coding RNAs play a key role in organizing the nucleus into functional subcompartments. By combining fluorescence microscopy and RNA deep-sequencing-based analysis, we found that RNA polymerase II transcripts originating from intronic Alu elements (aluRNAs) were enriched in the nucleolus. Antisense-oligo-mediated depletion of aluRNAs or drug-induced inhibition of RNA polymerase II activity disrupted nucleolar structure and impaired RNA polymerase I-dependent transcription of rRNA genes. In co ...[more]

PMID: 26464461

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Alu element-containing RNAs maintain nucleolar structure and function

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