In eukaryotes, precursor mRNAs (pre-mRNA) produce a unique class of biologically active molecules namely circular RNAs (circRNAs) with a covalently closed-loop structure via back-splicing. Because of this unconventional circular form, circRNAs exhibit much higher stability than linear RNAs due to the resistance to exonuclease degradation and thereby play exclusive cellular regulatory roles. Recent studies have shown that circRNAs are widely expressed in eukaryotes and display tissue- and disease-specific expression patterns, including in the cardiovascular system. Although numerous circRNAs are discovered by in silico methods, a limited number of circRNAs have been studied. This review intends to summarize the current understanding of the characteristics, biogenesis, and functions circRNAs and delineate the practical approaches for circRNAs investigation. Moreover, we discuss the emerging roles of circRNAs in cardiovascular diseases.

在真核生物中，前体 mRNA (pre-mRNA) 通过反向剪接产生一类独特的生物活性分子，即具有共价闭环结构的环状 RNA (circRNA)。由于这种非常规的环状形式，由于对核酸外切酶降解的抵抗力，circRNA 表现出比线性 RNA 更高的稳定性，从而发挥独特的细胞调节作用。最近的研究表明，circRNA 在真核生物中广泛表达，并显示出组织和疾病特异性的表达模式，包括在心血管系统中。虽然许多 circRNA 是通过in silico发现的方法，已经研究了有限数量的circRNA。本综述旨在总结目前对 circRNA 的特征、生物发生和功能的理解，并描述 circRNA 研究的实用方法。此外，我们讨论了 circRNA 在心血管疾病中的新作用。