Fig. 1.

Biogenesis and biological roles of long non-coding RNAs (lncRNAs). LncRNAs are mainly transcribed by RNA polymerase II and have an mRNA-like structure, typically with a 7mC cap at the 5′ end and a polyA tail at the 3′ end. a Some lncRNAs promote or suppress gene expression at transcriptional levels. b Some lncRNAs regulate gene expression by assembling chromatin-modifying complexes. c lncRNAs located in the cytoplasm participate in posttranscriptional gene regulation. d lncRNAs can act as miRNA sponges. e lncRNAs interact with proteins