Abstract
Interrogating individual two-dimensional (2D) cryo-EM images for the presence of defined three-dimensional (3D) structures that correspond to previously known (or predicted) macromolecular complexes is very challenging, but offers attractive opportunities for the analysis of large numbers of specimens. The work of Zhang et al. [(2025), IUCrJ, 12, 155-176] represents a significant step forward towards this goal.