Decreased stathmin expression ameliorates neuromuscular defects but fails to prolong survival in a mouse model of spinal muscular atrophy

► The role of stathmin in SMA is addressed by crossing SMA mice into stathmin knockout background. ► Heterozygous stathmin knockout improves motor performance and muscle pathology. ► The improvements observed in SMA mice are likely due to the recovery of microtubules in axons. ► Stathmin knockout cannot prevent the death of severe type SMA mice. ► Stathmin involves in the axonal defects in SMA, but is not associated with the death of SMA mice.