Abstract

Stress granules (SGs) are cytoplasmic ribonucleoprotein assemblies formed under stress conditions and are related to various biological processes and human diseases. Previous studies have reported the regulatory role of some proteins and linear RNAs in SG assembly. However, the relationship between circular RNAs and SGs has not been discovered. Here, we screened both linear and circular RNAs in SGs using improved total RNA sequencing of purified SG cores in mammalian cells and identified circular transcripts specifically localized in SGs. Circular RNAs with higher SG-related RBP binding abilities are more likely to be enriched in SGs. Furthermore, some SG-enriched circular RNAs are differentially expressed in hepatocellular carcinoma and adjacent tissues. These results suggest the regulatory role of circular RNAs in SG formation and provide insights into the biological function of circular RNAs and SGs in hepatocellular carcinoma.