Introduction

This tutorial provides an introduction to the use of relion-4.0 for cryo-EM structure determination. This tutorial covers the entire single-particle analysis workflow in relion-4.0: beam-induced motion-correction, CTF estimation; automated particle picking; particle extraction; 2D class averaging; automated 2D class selection; SGD-based initial model generation; 3D classification; high-resolution 3D refinement; CTF refinement and higher-order aberration correction; the processing of movies from direct-electron detectors; and final map sharpening and local-resolution estimation. Carefully going through this tutorial should take less than a day (if you have a suitable GPU or if you follow our precalculated results). After that, you should be able to run relion on your own data.

This tutorial uses a test data set on beta-galactosidase that was kindly given to us by Takayuki Kato from the Namba group at Osaka university, Japan. It was collected on a JEOL CRYO ARM 200 microscope. The data and our precalculated results may be downloaded and unpacked using the commands below. The full data set is also available at EMPIAR-10204.

wget ftp://ftp.mrc-lmb.cam.ac.uk/pub/scheres/relion30_tutorial_data.tar
wget ftp://ftp.mrc-lmb.cam.ac.uk/pub/scheres/relion40_tutorial_precalculated_results.tar.gz
tar -xf relion30_tutorial_data.tar
tar -zxf relion40_tutorial_precalculated_results.tar.gz

If you have any questions about relion, first read this entire document, check the FAQ on the relion Wiki and the archives of the CCPEM mailing list. If that doesn’t help, subscribe to the CCPEM email list and use the email address above for asking your question.

Caution

Please, please, please, do not send us direct emails, as we can no longer respond to all of those.