Representation theoretic patterns in multi-frequency class averaging for three-dimensional cryo-electron microscopy
Representation theoretic patterns in multi-frequency class averaging for three-dimensional cryo-electron microscopy
复制标题
三维冷冻电子显微镜多频类平均的表示理论模式
DOI:
10.1093/imaiai/iaab012
复制
发表时间:
2021
期刊:
影响因子:
--
通讯作者:
Zhao, Zhizhen
中科院分区:
文献类型:
--
作者:
Fan, Yifeng;Gao, Tingran;Zhao, Zhizhen
We develop in this paper a novel intrinsic classification algorithm—multi-frequency class averaging(MFCA)—for classifying noisy projection images obtained from three-dimensional cryo-electron microscopy by the similarity among their viewing directions. This new algorithm leverages multiple irreducible representations of the unitary group to introduce additional redundancy into the representation of the optimal in-plane rotational alignment, extending and outperforming the existing class averaging algorithm that uses only a single representation. The formal algebraic model and representation theoretic patterns of the proposed MFCA algorithm extend the framework of Hadani and Singer to arbitrary irreducible representations of the unitary group. We conceptually establish the consistency and stability of MFCA by inspecting the spectral properties of a generalized local parallel transport operator through the lens of Wigner-matrices. We demonstrate the efficacy of the proposed algorithm with numerical experiments.