FIGURE 4.

General biological properties of placenta-derived circRNAs. (A) Agarose gel electrophoresis of circRNA and linear RNA amplification products. (B) Total RNA-derived cDNA revealed successful amplification of circRNA, while the polyA⁺ RNA-derived cDNA did not. Four circRNAs were examined, and the corresponding linear transcripts were used as controls. (C) Analysis of circRNA resistance to RNase R digestion. Two circRNAs were examined, and the two corresponding linear RNAs were used as controls. (D) Human placental tissue-derived circRNAs were stably expressed within 24 h, while the corresponding linear transcripts degraded rapidly.