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Likelihood-based docking of models into cryo-EM maps.

ABSTRACT: Optimized docking of models into cryo-EM maps requires exploiting an understanding of the signal expected in the data to minimize the calculation time while maintaining sufficient signal. The likelihood-based rotation function used in crystallography can be employed to establish plausible orientations in a docking search. A phased likelihood translation function yields scores for the placement and rigid-body refinement of oriented models. Optimized strategies for choices of the resolution of data from the cryo-EM maps to use in the calculations and the size of search volumes are based on expected log-likelihood-gain scores computed in advance of the search calculation. Tests demonstrate that the new procedure is fast, robust and effective at placing models into even challenging cryo-EM maps.

SUBMITTER: Millan C

PROVIDER: S-EPMC10071562 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature

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Likelihood-based docking of models into cryo-EM maps.

Millán Claudia C McCoy Airlie J AJ Terwilliger Thomas C TC Read Randy J RJ

Acta crystallographica. Section D, Structural biology 20230315 Pt 4

Optimized docking of models into cryo-EM maps requires exploiting an understanding of the signal expected in the data to minimize the calculation time while maintaining sufficient signal. The likelihood-based rotation function used in crystallography can be employed to establish plausible orientations in a docking search. A phased likelihood translation function yields scores for the placement and rigid-body refinement of oriented models. Optimized strategies for choices of the resolution of dat ...[more]

PMID: 36920336

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