REgularised LIkelihood OptimisatioN  (RELION) employs an empirical Bayesian approach to refinement of (multiple) 3D reconstructions or 2D class averages in electron cryo-microscopy (cryo-EM). Briefly, the ill-posed problem of 3D-reconstruction is regularised by incorporating prior knowledge: the fact that macromolecular structures are smooth, i.e. they have limited power in the Fourier domain. In the corresponding Bayesian framework, many parameters of a statistical model are learned from the data, which leads to objective and high-quality results without the need for user expertise. 

It is developed in the group of Sjors Scheres at the MRC Laboratory of Molecular Biology

RELION is distributed under a GPLv2 license.  If RELION is useful in your work, please cite the papers below.





To see what versions of RELION are available type

module avail relion

To see what other modules are needed, what commands are available and how to get additional help type

module help  relion

To use RELION, include a command like this in your batch script or interactive session to load the relion module:

module load relion


Be sure you also load any other modules needed, as listed by the module help relion command.





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