Fig. 1

Illustration of the classifications of lncRNAs. a Sense lncRNAs are transcribed from the same strand of protein-coding genes, overlapping exons from the protein-coding genes. b Antisense lncRNAs are transcribed from the opposite strand of protein-coding genes, overlapping exons of protein-coding genes on the antisense strand. c Bidirectional lncRNAs are located on the opposite stand of protein-coding genes and transcribed from close proximity (less than 1000 base pairs) of their neighboring genes. d Intronic lncRNAs are derived entirely from introns of protein-coding genes. e Intergenic lncRNAs lie within intergenic regions. f Enhancer lncRNAs originate from the enhancer regions of protein-coding genes