Automated particle correspondence and accurate tilt-axis detection in tilted-image pairs.
Tilted electron microscope images are routinely collected for an ab initio structure reconstruction as a part of the Random Conical Tilt (RCT) or Orthogonal Tilt Reconstruction (OTR) methods, as well as for various applications using the "free-hand" procedure. These procedures all require identification of particle pairs in two corresponding images as well as accurate estimation of the tilt-axis used to rotate the electron microscope (EM) grid. Here we present a computational approach, PCT (particle correspondence from tilted pairs), based on tilt-invariant context and projection matching that addresses both problems. The method benefits from treating the two problems as a single optimization task. It automatically finds corresponding particle pairs and accurately computes tilt-axis direction even in the cases when EM grid is not perfectly planar.
Physical Biosciences Division, Lawrence Berkeley National Laboratory, CA 94720, USA. Electronic address: max.shatsky@gmail.com.
Maxim
M
Shatsky
Electrical Engineering and Computer Science Division, University of California, Berkeley, CA 94720, USA.
Pablo
P
Arbelaez
Life Sciences Division, Lawrence Berkeley National Laboratory, CA 94720, USA.
Bong-Gyoon
BG
Han
Life Sciences Division, Lawrence Berkeley National Laboratory, CA 94720, USA.
Dieter
D
Typke
Physical Biosciences Division, Lawrence Berkeley National Laboratory, CA 94720, USA; Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA.
Steven E
SE
Brenner
Electrical Engineering and Computer Science Division, University of California, Berkeley, CA 94720, USA.
Jitendra
J
Malik
Life Sciences Division, Lawrence Berkeley National Laboratory, CA 94720, USA.
Robert M
RM
Glaeser
D020285:Cryoelectron Microscopy / Q000295:instrumentation; D016969:Desulfovibrio vulgaris / Q000737:chemistry; D004926:Escherichia coli / Q000737:chemistry; D007168:IMP Dehydrogenase / Q000648:ultrastructure*; D007091:Image Processing, Computer-Assisted / Q000706:statistics & numerical data*; D021621:Imaging, Three-Dimensional / Q000295:instrumentation / Q000379:methods / Q000706:statistics & numerical data*; D012270:Ribosomes / Q000648:ultrastructure*
D007168:IMP Dehydrogenase
Particle correspondence; Tilt-axis detection; Tilted pairs