Fig. 5

Motor neuron projections in tardbp^Y220X/Y220X + MO larvae show increased number of orphaned presynaptic and postsynaptic puncta.

A, Representative images of single ventral root projection double-labelled for ZNP-1 (presynaptic marker, i) and sulforhodamine-conjugated αBTX (postsynaptic marker, ii). WT larvae display extensive co-localization of both ZNP-1 and αBTX (merged image, iii). Scale bar in (iii) and insets represent 25 μm and 10 μm respectively, arrowheads indicate orphaned ZNP-1 puncta and arrows indicate orphaned αBTX labelling. B, Quantification of the number synapses formed, quantified as the number of colocalized ZNP-1 and αBTX puncta. WT + MO (p < 0.05), tardbp^Y220X/Y220X (p < 0.01) and tardbp^Y220X/Y220X + MO larvae (p < 0.01) all had a significantly reduced number of synapses at the NMJ compared to WT larvae. C, Quantification of orphaned presynaptic ZNP-1 puncta over total number of ZNP-1 puncta. WT + MO, tardbp^Y220X/Y220X and tardbp^Y220X/Y220X + MO larvae displayed significantly higher proportion of orphaned ZNP-1 puncta compared to WT animals (p < 0.01). D, Quantification of orphaned postsynaptic αBTX staining over total number of αBTX puncta. tardbp^Y220X/Y220X + MO fish displayed significantly higher proportion of orphaned αBTX puncta compared to WT larvae (p < 0.05). Numbers in parentheses represent the number of somites analyzed for each treatment group. Data expressed as mean ± SEM: *p < 0.05; **p < 0.01.