jouvence, a new human snoRNA involved in the control of cell proliferation

The significance of small noncoding RNAs in the pathogenesis of cardiovascular diseases

With the advancement of high-throughput sequencing and bioinformatics, an increasing number of overlooked small noncoding RNAs (sncRNAs) have emerged. These sncRNAs predominantly comprise transfer RNA-derived fragments (tsRNAs), PIWI-interacting RNAs (piRNAs), Ro-associated non-coding RNAs (RNYs or Y-RNAs), small nucleolar RNAs (snoRNAs), and small nuclear RNAs (snRNAs). Each of these RNA types possesses distinct biological properties and plays specific roles in both physiological and pathological processes. The differential expression of sncRNAs substantially affects the occurrence and progression of various systemic diseases. However, their roles in the cardiovascular system remain unclear. Therefore, understanding the functionality and mechanisms of sncRNAs in the cardiovascular system holds promise for identifying novel targets and strategies for the diagnosis, prevention, and treatment of cardiovascular diseases. This review examines the biological characteristics of sncRNAs and their potential roles in cardiovascular diseases.

Small nucleolar RNAs promote the restoration of muscle differentiation defects in cells from myotonic dystrophy type 1

Recently, the repertoire of human small nucleolar noncoding RNAs (snoRNAs) and their potential functions has expanded with the discovery of new snoRNAs and messenger RNA (mRNA) targets, for which snoRNA-guided modifications may influence their stability, translatability, and splicing. We previously identified snoRNAs that are abundant in healthy human muscle progenitor cells. In this study, we demonstrated that SNORA40 and SNORA70 loss-of-function impairs myogenic differentiation. Interestingly, gain-of-function can rescue impaired differentiation muscle progenitor cells in myotonic dystrophy type 1 (DM1). We identified cyclin D3 (CCND3) mRNA, which is partially located in the nucleolus, as a target for SNORA40 and SNORA70, which are required for its pseudouridylated status. Expression of the CCND3 protein is required for muscle progenitors to exit the cell-cycle when they are induced to differentiate. We revealed that this switch requires SNORA40/70. Finally, we observed that DM1 cells show reduced levels of SNORA40/70 and undetectable CCND3 protein. However, restoring normal levels of SNORA40/70 partially restored CCND3 protein expression, coinciding with improved cell fusion capacity in DM1 muscle progenitors. Collectively, these data suggest that this effect may stem from SNORA40/70-dependent pseudouridylation of CCND3 mRNA, emphasizing snoRNAs as key players in normal and pathological muscle differentiation.

SnoRNAs: Exploring Their Implication in Human Diseases

Small nucleolar RNAs (snoRNAs) are earning increasing attention from research communities due to their critical role in the post-transcriptional modification of various RNAs. These snoRNAs, along with their associated proteins, are crucial in regulating the expression of a vast array of genes in different human diseases. Primarily, snoRNAs facilitate modifications such as 2'-O-methylation, N-4-acetylation, and pseudouridylation, which impact not only ribosomal RNA (rRNA) and their synthesis but also different RNAs. Functionally, snoRNAs bind with core proteins to form small nucleolar ribonucleoproteins (snoRNPs). These snoRNAs then direct the protein complex to specific sites on target RNA molecules where modifications are necessary for either standard cellular operations or the regulation of pathological mechanisms. At these targeted sites, the proteins coupled with snoRNPs perform the modification processes that are vital for controlling cellular functions. The unique characteristics of snoRNAs and their involvement in various non-metabolic and metabolic diseases highlight their potential as therapeutic targets. Moreover, the precise targeting capability of snoRNAs might be harnessed as a molecular tool to therapeutically address various disease conditions. This review delves into the role of snoRNAs in health and disease and explores the broad potential of these snoRNAs as therapeutic agents in human pathologies.

Non-coding RNA crosstalk with nuclear receptors in liver disease

The dysregulation of nuclear receptors (NRs) underlies the pathogenesis of a variety of liver disorders. Non-coding RNAs (ncRNAs) are defined as RNA molecules transcribed from DNA but not translated into proteins. MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are two types of ncRNAs that have been extensively studied for regulating gene expression during diverse cellular processes. NRs as therapeutic targets in liver disease have been exemplified by the successful application of their pharmacological ligands in clinics. MiRNA-based reagents or drugs are emerging as flagship products in clinical trials. Advancing our understanding of the crosstalk between NRs and ncRNAs is critical to the development of diagnostic and therapeutic strategies. This review summarizes recent findings on the reciprocal regulation between NRs and ncRNAs (mainly on miRNAs and lncRNAs) and their implication in liver pathophysiology, which might be informative to the translational medicine of targeting NRs and ncRNAs in liver disease.