Insights into organelle forming <scp>RNAs</scp> : Diversity, functions and future perspectives

RNA molecules play diverse and essential roles in cellular processes beyond their well-known functions in gene expression and regulation. While ribosomal RNAs (rRNAs) have long been recognized as structural components of ribosomes, recent research has highlighted the importance of a distinct group of RNAs which directly compose the structures or organelles in mammalian cells. We refer to these as 'organelle formation RNAs'. Specifically, the discovery of tubulin-associated lncRNA (TubAR), the first identified cytoskeleton-forming RNA, has expanded our understanding of RNA functionality; we now recognize 'organelle formation RNAs' not only as regulatory molecules but also as direct structural components within cellular subunits. Other 'organelle formation RNAs' include paraspeckle-forming RNAs, nuclear speckle-forming RNAs, and nucleolus-forming RNAs. Various RNAs contribute to the formation of distinct cellular structures, while also participating in intricate intermolecular interactions. Understanding these molecules not only uncovers their fundamental roles in cellular physiology but also suggests potential applications in the treatment of related diseases. By examining the latest advancements and methodologies in organelle formation RNA research, this review provides a comprehensive overview of the intricate mechanisms of these RNAs and future directions in the field.