MRNA stability influences gene expression and translation in almost all living organisms, and the levels of mRNA molecules in the cell are determined by a balance between production and decay. Maintaining an accurate balance is crucial for the correct function of a wide variety of biological processes and to maintain an appropriate cellular homeostasis. Long non-coding RNAs (lncRNAs) have been shown to participate in the regulation of gene expression through different molecular mechanisms, including mRNA stabilization. In this review we provide an overview on the molecular mechanisms by which lncRNAs modulate mRNA stability and decay. We focus on how lncRNAs interact with RNA binding proteins and microRNAs to avoid mRNA degradation, and also on how lncRNAs modulate epitranscriptomic marks that directly impact on mRNA stability.

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the gastrointestinal tract that develops due to the interaction between genetic and environmental factors. More than 160 loci have been associated with IBD, but the functional implication of many of the associated genes remains unclear. N6-Methyladenosine (m6A) is the most abundant internal modification in mRNA. m6A methylation regulates many aspects of mRNA metabolism, playing important roles in the development of several pathologies. Interestingly, SNPs located near or within m6A motifs have been proposed as possible contributors to disease pathogenesis. We hypothesized that certain IBD-associated SNPs could regulate the function of genes involved in IBD development via m6A-dependent mechanisms. We used online available GWAS, m6A and transcriptome data to find differentially expressed genes that harbored m6A-SNPs associated with IBD. Our analysis resulted in five candidate genes corresponding to two of the major IBD subtypes: UBE2L3 and SLC22A4 for Crohn’s Disease and TCF19, C6orf47 and SNAPC4 for Ulcerative Colitis. Further analysis using in silico predictions and co-expression analyses in combination with in vitro functional studies showed that our candidate genes seem to be regulated by m6A-dependent mechanisms. These findings provide the first indication of the implication of RNA methylation events in IBD pathogenesis.

N6-methyladenosine (m6A) RNA modifications and reovirus infections have recently been implicated in the development of celiac disease. While viral infections are known to alter the RNA modification machinery of the host, their interplay in autoimmune tissue damage remains unexplored. In this study we employed an in vitro model combining a viral mimic with gliadin peptides to simulate celiac disease conditions, alongside the analysis of serum and intestinal biopsies from controls and patients to investigate the link between m6A methylation and viral infections in inducing autoimmune inflammation. We found elevated anti-reovirus reactivity in patients, increased antiviral gene expression and enhanced m6A levels. Notably, the expression of IRF7 was synergistically induced by the combined exposure to the viral mimic and gliadin peptides, and this is mediated through m6A methylation in its coding region and interaction with the reader protein YTHDC2. Furthermore, the reduction of m6A through METTL3 silencing or simvastatin treatment reduced IRF7 mRNA methylation and downstream proinflammatory gene expression both in vitro and ex vivo. These findings highlight m6A methylation as a modulator of antiviral responses and a potential therapeutic target in autoimmune disorders.

M6A RNA modifications and reovirus infections have recently been involved in the development of celiac disease. Moreover, viral infections are linked to alterations in the RNA modification machinery of the host, but the link between these two events has not been studied in the context of autoimmunity driven tissue damage. Here we used an in vitro model of viral mimic combined with gliadin peptides, resembling celiac disease, together with sera and intestinal biopsies of controls and patients to describe the relationship between m6A methylation and viral infections in inducing autoimmunity related inflammation. We found elevated anti-reovirus reactivity in patients, together with higher antiviral gene expression and m6A induction. Additionally, we described a synergistic increase of IRF7 expression upon simultaneous exposure to the viral mimic and gliadin peptides is mediated by the presence of m6A motifs within its CDS and interaction with YTHDC2 reader protein. Furthermore, our findings revealed that reduction of m6A by METTL3 silencing or simvastatin treatment reduce IRF7 methylation and downstream inflammatory gene expression in vitro and ex vivo, opening new avenues for therapeutic interventions in autoimmune disorders.