Mitochondrial density in SMA presynaptic terminals is reduced.
A–D. The upper panels (A & C) show Z-stack projections while the lower panels (B & D) show single confocal sections. The staining from left to right are: BTX-A647 (grey), SVs (green), mitotracker (red), merge of SV and mitochondria. Data are from the TVA muscle (P14). E. Nearest neighbor distributions of SV clusters and mitochondrial regions (calculated from their respective center of mass), in WT and mutants terminals. F. Relationship between mean areas covered by SV and mitochondria in WT (blue symbol) and SMNΔ7 (red symbol) terminals. Scale bars A-D: 5 µm; insets: 600 nm.