LINC00205 acts as a multivalent scaffold promoting FUSP525L recruitment into Amyotrophic Lateral Sclerosis stress granules

Stress granules (SG) are dynamic, membrane-less ribonucleoprotein assemblies that orchestrate cellular stress responses and rapidly disassemble upon stress relief. In Amyotrophic Lateral Sclerosis (ALS), mutations in RNA-binding proteins such as Fused in Sarcoma (FUS) impair SG dynamics, promoting the formation of aberrant and persistent granules. Although long non-coding RNAs (lncRNAs) are emerging as regulators of ribonucleoprotein organization, their mechanistic role in SG architecture and pathological remodeling remains largely unexplored. Here, we identify LINC00205 as a critical RNA regulator of pathological SG dynamics in FUSP525L-associated ALS. Using Neuroblastoma cells and human iPSC-derived Motor Neurons (MN), we show that LINC00205 is enriched in SG upon oxidative stress and directly interacts with mutant FUSP525L. Knock-out of LINC00205 selectively reduces the formation of FUSP525L-containing SG and restores physiological SG disassembly kinetics, without affecting normal SG or FUS expression levels. Mechanistically, LINC00205 acts as a multivalent RNA scaffold, directly binding mRNAs specifically enriched in pathological SG, such as PLCXD3 and PIK3CA, as well as the RNA helicase DHX36, which is preferentially associated with FUSP525L-containing SG. We demonstrate that LINC00205 promotes their specific recruitment into pathological SG, thereby contributing to the aberrant features of these assemblies. Together, our findings uncover an active lncRNA-driven mechanism that shapes the molecular composition of aberrant ALS-related SG and regulates their persistence, establishing lncRNAs as key organizers of RNA-protein assemblies under stress and providing a conceptual framework for modulating pathological condensates.