Fig. 3. Accumulation of CCVs and empty clathrin cages in nerve terminals of Aux-KO, SJ1-KI^RQ, and Aux-KO/SJ1-KI^RQ mice.

a Representative EM micrographs of nerve terminals from the dorsal striatum of single and double mutant mice. Red and black arrows point to CCVs and empty clathrin coated cages (EC) respectively. Scale bar: 250 nm. b Morphometry analysis of the number of SVs, sum of number of CCVs and ECs, CCVs, as well as ECs per pre-synaptic area in the dorsal striatum (Ctrl n = 124, Aux-KO n = 156, SJ1-KI^RQ n = 198, and Aux-KO/SJ1-KI^RQ n = 120). Each dot represents one nerve terminal. Data are represented as mean ± SEM. *p < 0.05, **p < 0.01, ****p < 0.0001 (One-way ANOVA with Games-Howell’s multiple comparison test). c Examples of Purkinje nerve terminals in the deep cerebellar nuclei of Aux-KO/SJ1-KI^RQ mouse showing the striking accumulation of assembled clathrin (both ECs and CCVs). The tight packaging of SVs (middle and right images) was previously reported in nerve terminals of SJ1-KI^RQ mice (¹³ Fig. S3d) and may reflect dystrophic changes, Scale bar: 500 nm.