Fig. 2

Gastrocnemius NMJs show significant decreases in pre-synaptic area and pre- and post-synaptic colocalization in transgenic and knock-in models of SBMA. Pre-synaptic terminals were stained with synaptic vesicle marker synaptophysin and measured for pre-synaptic area and colocalization with post-synaptic membrane, labeled with fluorescently tagged a-bungarotoxin. Arrows point to NMJ with low synaptophysin staining. Synaptophysin image in A were merged with α-BTX images for panel D. A Gastrocnemius NMJs showed significantly decreased pre-synaptic area in transgenic and knock-in mice (B NTg vs Tg p < 0.0001; C WT vs KI p < 0.0001). D Gastrocnemius NMJs showed significantly decreased pre- and post-synaptic colocalization in transgenic and knock-in mice (E NTg vs Tg, p < 0.001; F WT vs KI, p < 0.01). Mann–Whitney Test was used to evaluate statistical significance for distributions. Abbreviations: NTg, non-transgenic; Tg, transgenic; WT, wild-type; KI, knock-in