Figure EV3. Representative micrographs of ventral horn neurons in non‐transgenic, SOD1^G85R, or Sig1R^−/− mice.

1. Immunofluorescence staining of mouse ventral horn neurons from non‐transgenic or Sig1R^−/− mice with anti‐PDI and NeuN antibodies. Note that general ER morphology was not affected by the Sig1R deficiency. Scale bars: 50 μm.
2. Representative low‐magnification electron micrographs of the MAM (arrows) in motor neurons of 12‐month‐old non‐transgenic (Non‐Tg), SOD1^G85R, or Sig1R^−/− mice. Scale bars: 500 nm.