Targeted expression of SMN in neuronal tissue protects against spinal motor neuron loss in SMA mice.

<p>(<b>A</b>) Western blot analysis of tissue from PND10–12 controls (1) and SMA mice with (2) or without (3) the Nes-Cre transgene. An increase in SMN protein is observed specifically in the brains and spinal cords of SMA mice harboring the Nes-Cre transgene (lanes 2 in figure). (<b>B</b>) Immunohistochemical analysis of lumbar motor neurons of PND7 controls and SMA mice with or without the Nes-Cre transgene. Loss of motor neurons observed in the <i>SMN2;Smn^Res/Res</i> mice is arrested in mutants expressing SMN in their neurons. (<b>C</b>) Quantification of lumbar motor neuron numbers in the above mice. *, <i>p</i><0.05, one-way ANOVA; n≥3 mice. (<b>D</b>) Immuno-histochemical analysis of motor neurons depicting the restoration of gems (arrows) in SMA mice expressing neuronal SMN. (<b>E</b>) Quantification of gems within motor neurons of controls and mutants with or without the Nes-Cre transgene. ***, <i>p</i><0.001, one-way ANOVA; n≥50 motor neurons. Note: Scale bars in panel (B) – 100 µm, panel (D) – 10 µm.