The Long Non-Coding RNA ANRIL in Cancers.

ANRIL (Antisense Noncoding RNA in the INK4 Locus), a long non-coding RNA encoded in the human chromosome 9p21 region, is a critical factor for regulating gene expression by interacting with multiple proteins and miRNAs. It has been found to play important roles in various cellular processes, including cell cycle control and proliferation. Dysregulation of ANRIL has been associated with several diseases like cancers and cardiovascular diseases, for instance. Understanding the oncogenic role of ANRIL and its potential as a diagnostic and prognostic biomarker in cancer is crucial. This review provides insights into the regulatory mechanisms and oncogenic significance of the 9p21 locus and ANRIL in cancer.

Purification of RiboNucleoProtein Particles by MS2-MBP Affinity Chromatography.

RiboNucleoProtein particles (RNPs), which are composed of RNAs and proteins, play essential roles in many biological processes. The isolation of these molecular machines is a critical step to better understand their mechanisms of action. In this chapter, we describe the MS2-MBP affinity chromatography used to purify the protein content of the RNPs formed with an RNA of interest in a nuclear extract. Substrate RNAs are furnished with a tag consisting of three stem-loops that provide specific binding sites for the phage MS2 protein. Here, we successfully applied this method to isolate RNPs formed with subfragments of the long noncoding RNA ANRIL (Antisense Noncoding RNA in the INK4 Locus).

Implication of repeat insertion domains in the trans-activity of the long non-coding RNA ANRIL.

Long non-coding RNAs have emerged as critical regulators of cell homeostasis by modulating gene expression at chromatin level for instance. Here, we report that the lncRNA ANRIL, associated with several pathologies, binds to thousands of loci dispersed throughout the mammalian genome sharing a 21-bp motif enriched in G/A residues. By combining ANRIL genomic occupancy with transcriptomic analysis, we established a list of 65 and 123 genes potentially directly activated and silenced by ANRIL in trans, respectively. We also found that Exon8 of ANRIL, mainly made of transposable elements, contributes to ANRIL genomic association and consequently to its trans-activity. Furthermore, we showed that Exon8 favors ANRIL's association with the FIRRE, TPD52L1 and IGFBP3 loci to modulate their expression through H3K27me3 deposition. We also investigated the mechanisms engaged by Exon8 to favor ANRIL's association with the genome. Our data refine ANRIL's trans-activity and highlight the functional importance of TEs on ANRIL's activity.