NORAD prevents axonal degeneration by orchestrating KLC1-mediated SFPQ transport via liquid-liquid phase separation

NORAD prevents axonal degeneration by orchestrating KLC1-mediated SFPQ transport via liquid-liquid phase separation Abstract Neuronal function requires precise long-distance axonal transport mediated by molecular motors and RNA-binding proteins like SFPQ, though regulatory mechanisms remain poorly defined. We identify long non-coding RNA NORAD as a master regulator of this process through liquid-liquid phase separation (LLPS). While SFPQ and kinesin-1 mediate cargo delivery, the specific RNA coordinating their interaction was unknown. We demonstrate NORAD directly binds kinesin light chain 1 (KLC1) and promotes SFPQ condensation into dynamic LLPS droplets, enabling efficient transport. CRISPR-assisted mapping and functional assays show NORAD depletion disrupts granule dynamics, impairs neuroprotective mRNA localization, and induces axonal degeneration. In vitro reconstitution confirms NORAD-KLC1 synergy enhances SFPQ phase separation, and neuron-specific knockout mice exhibit motor deficits with reduced neuronal density. These findings establish the first evidence of lncRNA NORAD-mediated LLPS in axonal transport, revealing a new paradigm for RNA-guided neuronal maintenance. Subject Area - Biochemistry (17690) - Bioengineering (13892) - Bioinformatics (41936) - Biophysics (21451) - Cancer Biology (18588) - Cell Biology (25499) - Clinical Trials (138) - Developmental Biology (13378) - Ecology (19899) - Epidemiology (2067) - Evolutionary Biology (24320) - Genetics (15609) - Genomics (22506) - Immunology (17736) - Microbiology (40394) - Molecular Biology (17181) - Neuroscience (88603) - Paleontology (666) - Pathology (2832) - Pharmacology and Toxicology (4824) - Physiology (7641) - Plant Biology (15152) - Synthetic Biology (4294) - Systems Biology (9825) - Zoology (2271)