The raw stacks were over-exposed (>100 electrons per square angstrom), but after dose weighting using MotionCor2 and straightforward processing using RELION, a beautiful map of 20S proteasome emerged, with bulky side chains clearly resolved! The pdb model used here is 3j9i. It is docked with rigid body fitting in Chimera.

This is the first time that a sub 4 angstrom map is generated from our Talos F200C. Data was collected by Chang and Tian (Perozo Lab) manually using SerialEM. Thank Zanlin Yu at Yifan Cheng lab for providing the 20S proteasome.