Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease resulting from loss of both upper and lower motor neurons in the brain and spinal cord. ALS symptoms include diffuse muscle weakness, muscle atrophy, spasticity and hyperreflexia (upper), paralysis (lower), and 2-5 year life expectancy. One approach to combat ALS is delivery of neurotrophic factors to protect damaged motor neurons, but this is dependent upon expression and proper subcellular localization of key neurotrophin receptors. Neurotrophin receptor activity is dependent upon localization to specialized membrane microdomains termed membrane/lipid rafts (MLR). Our group has shown that caveolin-1 (Cav-1), an MLR-scaffolding protein, is neuroprotective, increases MLR-localization of neurotrophin receptors, and enhances mitochondrial health and adaptation to stress. Moreover, in vivo delivery of neuron-targeted Cav-1 (using a neuron-specific synapsin promoter [SynCav1]) increases MLR formation and neurotrophin receptor (e.g., TrkB) localization to MLR, enhances neuroplasticity, and significantly improves behavior. For proof-of-concept experiments, we generated a synapsin-driven Cav-1 overexpressing mouse (SynCav1 TG) and crossed it with a mouse that contains the human mutant superoxide dismutase 1 (hSOD1G93A) that is linked to ALS. When compared to hSOD1G93A, hSOD1G93A/SynCav1+ mice demonstrated preserved body weight and longer survival, greater motor evoked potentials (i.e., greater amplitude and lower latency), better running wheel performance, and more α motor neurons in the thoracic and lumbar vertebral column. Furthermore, mice had more MLR and MLR-associated TrkB in spinal cord tissue. Preliminary data show that subpial spinal cord delivery of AAV9-SynCav1 to hSOD1G93A rats improves MEP function and forelimb grip strength, which suggests that SynCav1 may be used as a novel therapeutic intervention to reverse neurodegenerative diseases such as ALS. Our overarching hypothesis is that SynCav1 gene delivery in vivo alone or in combination with a TrkB agonist will improve motor function and extend survival in a SOD1G93A mouse model of ALS. The New Paradigm that this project introduces lies in the approach of using a single genetic intervention, SynCav1 to 1) re-establish a polarized membrane signaling platform, 2) augment neurotrophin signaling, 3) enhance neuroplasticity, and 4) extend survival in the setting of ALS. Our study represents more than an incremental advancement in that it will use a novel gene therapy intervention combined with specific receptor-targeted pharmacology to restore and augment pro-growth signaling, axonal and dendritic growth, and formation of newly, functional synapses in the spinal cord of ALS models. The proposed research will attempt to use a novel genetic approach to harness the body’s natural potential for neuroplasticity and neuroregeneration. By over-expressing Cav-1 specifically ...