Pelco glow discharge cleaning system

For negative-stain electron microscopy, 4 μl of DELE1 samples at 0.1 mg ml⁻¹ were applied onto carbon coated 400 mesh Cu-Rh maxtaform grids (Electron Microscopy Sciences), which were plasma cleaned for 15 s using the Pelco glow discharge cleaning system (Ted Pella) with atmospheric gasses at 15 mA. The samples were stained using 2% (wt/vol) uranyl formate solution, then blotted and dried. For cryo-EM, 4 μl of WT DELE1^CTD sample at 3 mg ml⁻¹ was applied onto 300 mesh R1.2/1.3 UltraAuFoil holey gold grids (Quantifoil) that were plasma cleaned for 15 s using Pelco glow discharge cleaning system (Ted Pella) with atmospheric gasses at 15 mA. The grids were immediately vitrified by plunge-freezing using a Thermo Fisher Vitrobot Mark IV at 4 °C, 5 s, 100% humidity, and a blot force of 0 using Whatman grade 1 blotting paper.