The Survival of Motor Neurons (SMN) protein participates in RNA splicing. Decreases in SMN, typically a consequence of defects in the smn1 gene, result in the death of motor neurons and lead to the neurodegenerative disease, spinal muscular atrophy (SMA). Cuspin-1 is a small molecule upregulator of SMN that has been shown in vitro to increase levels of SMN in SMA patient fibroblasts by 50% at 18 μM. Its mechanism of action is thought to involve increased phosphorylation of ERK to initiate Ras-Raf-MEK signaling, which results in an increased rate of SMN translation.
