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RELION (for REgularised LIkelihood OptimisatioN, pronounce rely-on) is a stand-alone computer program that employs an empirical Bayesian approach to refinement of (multiple) 3D reconstructions or 2D class averages in electron cryo-microscopy (cryo-EM).

Relion Homepage

Available Modules

module load Relion/4.0.1-gimkl-2020a

Getting started with Relion is most easily done via its X11 GUI, which is launched with the command "relion".  

module load Relion

After the desired options have been selected press the "Check command" button to see the command it constructs in your terminal window. That command line can then be pasted into a Slurm batch script.

If you leave "Number of MPI procs" at 1 then the Relion GUI will produce a command like

which relion_run_ctffind ...

That will work but can be simplified to

relion_run_ctffind ...

If MPI is used then Relion will correctly recommend the MPI version of the tool, eg:

which relion_run_ctffind_mpi ...

but MPI programs need to be launched via srun, so that should be:

srun relion_run_ctffind_mpi ...

We have made some effort to integrate the Relion GUI directly with Slurm so that it can submit Slurm jobs directly, however this might not entirely work yet.

Some of the Relion tools benefit tremendously from using a GPU.

For licensing reasons we ask that you install the GPU accelerated MotionCorr2 yourself if you find Relion's own CPU-only version of the same algorithm insufficient.