LncRNA-mediated transcriptional regulation. Long non-coding RNAs (lncRNAs; red solid lines) regulate gene transcription through three main mechanisms: (A) Interaction with and recruitment of chromatin-modifying enzymes (e.g., histone methylases, acetylases, and deacetylases) to the target gene locus. Modulation of the chromatin state by these enzymes leads to activation or repression of local genes. (B) Interaction with other RNA-binding factors such as hnRNPs to form RNA–protein complexes (RNPs). RNPs can either promote transcription by recruiting key proteins to the target gene promoters or repress gene transcription by binding to existing gene repressors. (C) LncRNAs also have enhancer functions and help to change the chromatin architecture and recruit transcriptional machinery proteins to adjacent target gene locus to promote its transcription. (D) LncRNAs are also involved in the repression of some pro-apoptotic genes, such as FAS and BIK, by acting as a decoy for the transcription factor (NF-YA).