Figure 3.

Senescence regulation by lncRNAs. (a) LncRNAs recruit PRC1 and PRC2 complexes to target promoters to modulate senescence via gene silencing. Recruitment may be direct operating in cis (i.e., CBX7 directly binds nascent ANRIL at the INK4 locus) or indirect operating in trans via an adaptor molecule (i.e., PANDA‐mediated bridging between SAFA and BMI1 at target genes). (b) Noncoding transcription of TERRA at telomeres maintains telomere homeostasis by recruiting shelterin proteins (e.g., TRF2). In the absence of TRF2 (which occurs in replicative senescence due to telomere attrition), TERRA facilitates a DNA damage response (DDR) by recruiting an LSD1/MRE11 complex thus promoting senescence. Wavy blue lines indicate putative hybridization between lncRNA and a target promoter or other gene‐regulatory region.