In recent years following the COVID-19 pandemic, RNA has gained attention for its successes and potential use in vaccines and therapeutics. One avenue of interest in RNA research is a non-coding class of RNA first identified almost 50 years ago, circular RNA (circRNA).

In 1976, Sanger et al. first identified circRNA in plant viroids, and later additions to the field found them in mice, humans, nematodes, and other groups. Unlike linear RNA, circRNA are covalently closed loops that don’t have a 5′ cap or 3′ polyadenylated tail. Following its discovery, researchers thought circRNA was the product of a rare splicing event caused by an error in mRNA formation leading to low interest in researching the subject (1).

In the early 2010s, following the development of high throughput RNA sequencing technology, Salzman et al. determined that circRNAs were not a result of misplicing, but a stable, conserved, and widely sourced form of RNA with biological importance. Since noncoding RNA makes up the majority of the transcriptome it’s an incredibly important field of study. We now recognize circRNAs for their potential as disease biomarkers and importance in researching human disease (2).

Continue reading “Reviewing the Importance of circRNA”