Circular RNAs and Cardiovascular Regeneration

Abstract

circular RNAs (circRNAs) are a type of non-coding RNAs that are widely present in eukaryotic cells. They have the characteristics of stable structure, high abundance, and cell or tissue specific expression. circRNAs are single-stranded RNAs that are covalently back spliced to form closed circular loops. They may participate in gene expression and regulation through a variety of action modes. circRNAs can encode proteins or function by acting as miRNA sponges for protein translation. Since 2016, a growing number of research studies have shown that circRNAs play important role in the pathogenesis of cardiovascular disease. With the construction of circRNA database, the differential expression of circRNAs in the heart tissue samples from different species and the gradual elucidation of its mode of action in disease may become an ideal diagnosis biomarker and an effective therapeutic target. What can be expected surely has a broader application prospect. In this review, we summarize recent publications on circRNA biogenesis, expression profiles, functions, and the most recent studies of circRNAs in the field of cardiovascular diseases with special emphasis on cardiac regeneration.

The function and regulation network mechanism of circRNA in liver diseases

“…(3) RNA-binding protein (RBP)-driven circularization, in this model, RBP can promote the interaction between upstream introns and downstream introns, resulting in the production of ecircRNAs or EIciRNA [26]. (4) Lariat introns-driven circularization, the formation of the lasson introns-driven circularization mainly refers to the combination of the 7-nt GU rich element near the 5 splicing point and the 11-nt C-rich element near the 3′ branching point to escape the degradation of the debranching enzyme and form a stable ciRNA [27].…”

Non-Coding Ribonucleic Acids as Diagnostic and Therapeutic Targets in Cardiac Fibrosis

“…There are thousands of lncRNAs encoded in the human genome with a diversity of roles including direct gene enhancement or silencing, trafficking of nuclear factors, DNA repair, protein binding, sponging miRNAs, and others [12]. Like lncRNAs, circRNAs are 200 or more nucleotidelong sequences with high regulatory versatility and a unique, highly stable closed-loop structure [13]. CircRNAs also express a broad range of regulatory capabilities, often by sponging miRNAs, but also by acting as reservoirs, binding proteins directly, recruiting proteins to specific cellular sites, encoding micropeptides, and producing daughter ncRNAs [14,15].…”

Identification of circular RNAs regulating cardiomyocyte proliferation in neonatal pig hearts

“…Circular RNA (circRNA) is a type of RNA molecule that forms a closed loop structure. circRNAs are divided into four categories: ecRNAs (exonic circRNAs) which are derived from single or multiple exons, ciRNAs (circular intronic RNAs) which are derived from introns, EIciRNAs (exon-intron circRNAs) which are composed of exons and introns, and tricRNAs (tRNA intronic circRNAs) which are formed by splicing tRNA introns (4).…”

“…This stability allows circRNAs to accumulate in cells, making them potential biomarkers for various cardiovascular conditions. circRNAs carry out their functions through mechanisms related to transcription regulation, such as miRNA sponging, formation of RNA-protein complexes, and interactions with RNA-binding proteins (RBPs) (4,8). circRNAs can act as microRNA sponges, binding to and sequestering miRNAs, thus preventing them from binding to their target mRNAs and suppressing gene expression.…”