Figure 10. Specific anti-SUMO1 immunolabelling in His6-HA-SUMO1 KI neurons permeabilised with Triton X-100 is mainly nuclear and not in synaptic boutons.
Hippocampal neurons from either His6-HA-SUMO1 KI mice or SUMO1 KO mice were fixed in 4% PFA and permeabilised using 0.3% Triton X-100. Primary antibodies were 1:50 mouse anti-SUMO1 (green), 1:2000 rabbit anti-synapsin 1/2 (red), and 1:500 chicken anti-Map2 (blue). In His6-HA-SUMO1 KI neurons but not in SUMO1 KO neurons, anti-SUMO1 labelling was observed in nuclei (arrows). Additional anti-SUMO1 labelling was observed similarly in both His6-HA-SUMO1 KI and SUMO1 KO samples, which did not appear to correspond with synapsin-positive puncta (arrowheads). Data are representative of 5 independent experiments. Scale bars, 10 μm.