SmnX7/Smn73Ao third instar larvae have significantly increased evoked excitatory postsynaptic potential amplitude at the neuromuscular junction.
Smn73Ao mutant larvae exhibit an aberrant increase in evoked excitatory postsynaptic potential amplitudes at the neuromuscular junction to ~125% of controls.
Smn73Ao/Smnf01109 third instar larvae show significant decreases in bouton number (per muscle area) compared to either heterozygote (heterozygotes are similar to controls).
Homozygous larvae are thinner and shorter than control larvae at 4 days after egg laying.
Homozygous second-third instar larvae show impaired motor function, showing a smaller distance travelled in the 20 seconds after movement was stimulated with a needle than control larvae.
Most homozygotes die between the second and third larval stages, with less than 10% reaching the third instar larval stage.
Smn73Ao/Smnf01109 third instar larvae show a reduction in bouton number per muscle area at the neuromuscular junction compared to wild type.
Homozygous larvae show a progressive loss of mobility and increased uncoordinated movement before death occurs at the late larval stage. Homozygous larvae show a 53 +/- 5% decrease in contraction rate compared to control third instar larvae. Females carrying homozygous germline clones lay only a few eggs, which die at very early stages (between 0 and 4 hours after egg laying at 25oC). Excitatory postsynaptic currents are reduced in amplitude in mutant third instar larvae compared to control animals. Mutant larvae show defects at the neuromuscular junction; an increased number of enlarged boutons is seen.