Extended Data Fig. 3: Cryo-EM analysis of the postfusion S2 trimer.
From: Cryo-EM structure of SARS-CoV-2 postfusion spike in membrane

Top, representative micrograph out of ~30,000 similar micrographs, and 2D averages (box dimension: 500 Å) of the cryo-EM particle images of the postfusion S2 trimer in nanodiscs. Bottom, data processing workflow for structure determination.