CryoAlign: feature-based method for global and local 3D alignment of EM
  density maps
Bintao He Fa Zhang Chenjie Feng Jianyi Yang Xin Gao Renmin Han
Advances on cryo-electron imaging technologies have led to a rapidly
increasing number of density maps. Alignment and comparison of density maps
play a crucial role in interpreting structural information, such as
conformational heterogeneity analysis using global alignment and atomic model
assembly through local alignment. Here, we propose a fast and accurate global
and local cryo-electron microscopy density map alignment method CryoAlign,
which leverages local density feature descriptors to capture spatial structure
similarities. CryoAlign is the first feature-based EM map alignment tool, in
which the employment of feature-based architecture enables the rapid
establishment of point pair correspondences and robust estimation of alignment
parameters. Extensive experimental evaluations demonstrate the superiority of
CryoAlign over the existing methods in both alignment accuracy and speed.