Figure 1.

Current classification of long noncoding RNAs (lncRNAs) based on the positional relationship between lncRNAs and adjacent protein‐encoding genes. A, Sense lncRNAs partially overlap with protein‐coding genes. B, Intronic lncRNAs are located on an intron of the target gene. C, Intergenic lncRNAs are located between two protein‐coding genes (<10 kb apart from the target gene). D, Antisense IncRNAs are located on the negative strand and partially or completely overlap with the protein‐coding gene. E, Bidirectional lncRNAs are located on the negative strand, which are transcribed in the opposite direction, but does not overlap with the target gene. Arrows indicate the direction of gene transcription. Genomic DNA plus (+) and minus (−) strands are labeled accordingly. The target gene of sense lncRNA, intronic lncRNA, and antisense lncRNA is shown in panel B and that of intergenic lncRNA and bidirectional lncRNA is shown in panel C