Finally, we report that clock disruption through cholinergic neuron-specific deletion of clock activator BMAL1 (i) increases lumbar spinal cord motor neuron loss and sciatic nerve axon degeneration and (ii) drives time-of-day-dependent alternative splicing of genes associated with RNA processing, including genes encoding ALS-linked RBPs (e.g., Matr3, Srsf7, and Ythdf2). This evidence concerns the gene MATR3 and amyotrophic lateral sclerosis.