FIGURE 1.

Categorizing lncRNAs based on subcellular localization and site of action. (a) Left—following transcription, trans‐acting lncRNA localize to distant sites within the nucleus and/or are exported to the cytoplasm; right—NORAD largely localizes to the cytoplasm, where it interacts with PUM proteins to form phase‐separated condensates known as NP bodies (Elguindy & Mendell, 2021; Lee et al., 2016), while MALAT1 remains within the nucleus and localizes to nuclear speckles (Hutchinson et al., 2007); (b) Left—cis‐acting lncRNAs accumulate at or near their site of transcription. Right—XIST (red) is expressed from and spreads on the inactive (Xi) but not the active (Xa) X chromosome (green) in female mammalian cells. The lncRNA AIRN (red) is expressed from and represses the expression of genes from the imprinted IGF2R locus (green) on the paternal (Pa) but not maternal (Ma) allele