出版社:Academy & Industry Research Collaboration Center (AIRCC)
摘要:The knowledge of structure of proteins, protein derived compounds and RNA structures in
eukaryotic cell is mandatory to understand the functions of these macromolecules.With recent
development of Direct Electron Detector Device (DDD) camera and application of maximum
likelihood algorithms in volume reconstruction,cryo Electron Microscopy (cryo-EM) enables us
to visualize the macromolecules in nearly physiological state. The current resolution limit of
cryo-EM can be improved further by applying novel and effective signal processing algorithms
after the EM workflow. In this work, a signal processing method has been developed to enhance
the resolution of the EM volume through volume restoration techniques. We have proposed a
novel technique to estimate the volume degradation function of the volume reconstruction
system from the noise-only subvolumes of the observed EM volume. Then the volume is restored
(utilizing the estimated volume degradation function) using a combination of regularized
Richardson-Lucy and Wiener Deconvolution techniques. In addition to volume restoration, we
have employed spatial de-noising techniques utilizing various morphological filters to reduce
noise outside the main molecular structure. The experimental results demonstrate that the
resolution (evaluated by ourier Shell Correlation curve) and visual quality of the EM volume
can be significantly improved using our proposed technique.
关键词:Electron Microscopic Signal processing Visualization volume degradation function Image;processing