Fig. 1From: Enhancer RNAs: mechanisms in transcriptional regulation and functions in diseasesBiological characteristics of eRNAs. A Most eRNAs are bidirectional transcribed, which called 2d-eRNAs and with length within 0.5–2 kb, they are unspliced and nonpolyadenylated. B About 10% of eRNAs are unidirectionally transcribed (1d-eRNAs), which average length is more than 4 kb, and they are spliced and polyadenylatedBack to article page