Control of nucleolar stress and translational reprogramming by lncRNAs

Under adverse environmental conditions, cells activate stress responses that favour adaptation or, in case of irreversible damage, induce cell death. Multiple stress response pathways converge to downregulate ribosome biogenesis and translation since these are the most energy consuming processes in the cell. This adaptive response allows preserving genomic stability and saving energy for the recovery. It follows that the nucleolus is a major sensor and integrator of stress responses that are then transmitted to the translation machinery through an intricate series of conserved events. Long non-coding RNAs (lncRNAs) are emerging as important regulators of stress-induced cascades, for their ability to mediate post-transcriptional responses. Consistently, many of them are specifically expressed under stress conditions and a few have been already functionally linked to these processes, thus further supporting a role in stress management. In this review we survey different archetypes of lncRNAs specifically implicated in the regulation of nucleolar functions and translation reprogramming during stress responses. (AU)