Circular RNA-seq of lung adenocarcinoma cell line: negative control A549
Total RNAs from A549 cells were firstly treated with RNase R to remove other non-circular RNAs. Then the treated RNAs were prepared to enrich circRNA and remove ribosomal RNA (rRNA) using CircRNA Enrichment Kit (Cloud-seq Inc, USA). RNA libraries were constructed by using pretreated RNAs with TruSeq Stranded Total RNA Library Prep Kit (RS-122-2201; Illumina, San Diego, CA, USA)