Annuaire
Conformational space exploration of cryo-EM structures by variability refinement.
Biochim Biophys Acta Biomembr, 1865(4):184133.
Cryo-EM observation of biological samples enables visualization of sampleheterogeneity, in the form of discrete states that are separable, or continuousheterogeneity as a result of local protein motion before flash freezing.Variability analysis of this continuous heterogeneity describes the variancebetween a particle stack and a volume, and results in a map series describing thevarious steps undertaken by the sample in the particle stack. While thisobservation is absolutely stunning, it is very hard to pinpoint structuraldetails to elements of the maps. In order to bridge the gap between observationand explanation, we designed a tool that refines an ensemble of structures intoall the maps from variability analysis. Using this bundle of structures, it iseasy to spot variable parts of the structure, as well as the parts that are notmoving. Comparison with molecular dynamics simulations highlights the fact thatthe movements follow the same directions, albeit with different amplitudes.Ligand can also be investigated using this method. Variability refinement isavailable in the Phenix software suite, accessible under the program namephenix.varref.
Actions sur le document
