• embryos are developmentally delayed at E9.5

• die between E9.5 and E12.5

• median survival of 12 days

• neuromuscular junctions are similar to controls in the intercostal and triangularis sterni muscles (J:183080)

• decrease in cardiac autonomic innervation

• in L3-L5 spinal cord sections but not in the cervical or thoracic regions

• by P9

• end-stage mice display skipped or dropped beats

• at P9-P11

• at P9-P11

• ambulatory throughout life (J:183080)

• lateral instability of the hind limbs

• significantly improved righting response

• early in life

• outgrow this passive behavior after P6

• median survival is 7 days

• significant decrease in the number of fully innervated motor endplates and increase in the number of partially innervated and denervated endplates in the intercostal muscle

• however, innervation of the endplates in the triangularis sterni muscle is similar to controls

• increase in intercostal muscle homogeneous motor endplates and decrease in the number of endplates containing secondary structure

• however, endplates in the triangularis sterni muscle are similar to controls

• decrease in the number of glutamatergic excitatory synapses at P5 in the L2-L5 region of the spinal cord

• decrease in the number of glutamatergic excitatory synapses at P5 in the L2-L5 region of the spinal cord

• significant loss in average MNs per ventral horn is seen in cervical, thoracic, and lumbar spinal cords

• significant loss in average MNs per ventral horn is seen in cervical, thoracic, and lumbar spinal cords

• signs of neurodegeneration in the intercostal muscle

• threshold voltage in motor neurons is significantly lower and amplitude of the persistent inward current is significantly larger indicating increased excitability in cultured motor neurons

• high frequency of postsynaptic potentials in cultured motor neurons

• by P3 and declines over time

• at P3-P7

• at P3-P7

• at P3-P7

• decreased motor function

• never develop the ability to right when placed on the back

• near complete paralysis by P5

• at P2 or later

• viable and indistinguishable from control littermates