Optimizing weighting functions for cryo-electron microscopy

Jing Cheng; Xinzheng Zhang

doi:10.52601/bpr.2021.210001

Volume 7 Issue 2

Feb. 2021

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Jing Cheng, Xinzheng Zhang. Optimizing weighting functions for cryo-electron microscopy. Biophysics Reports, 2021, 7(2): 152-158. doi: 10.52601/bpr.2021.210001

Citation:

Jing Cheng, Xinzheng Zhang. Optimizing weighting functions for cryo-electron microscopy. Biophysics Reports, 2021, 7(2): 152-158. doi: 10.52601/bpr.2021.210001

Jing Cheng, Xinzheng Zhang. Optimizing weighting functions for cryo-electron microscopy. Biophysics Reports, 2021, 7(2): 152-158. doi: 10.52601/bpr.2021.210001

Citation:

Jing Cheng, Xinzheng Zhang. Optimizing weighting functions for cryo-electron microscopy. Biophysics Reports, 2021, 7(2): 152-158. doi: 10.52601/bpr.2021.210001

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Optimizing weighting functions for cryo-electron microscopy

doi: 10.52601/bpr.2021.210001

Jing Cheng^{1, 2},
Xinzheng Zhang^{1, 2, 3
,
,}

1.
National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
2.
University of Chinese Academy of Sciences, Beijing 100049, China
3.
Center for Biological Imaging, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China

Funds: We thank L. Kong for cryo-EM data storage and backup, and Dr. Richard Haase, from Liwen Bianji, Edanz Group China (www.liwenbianji.cn/ac), for editing the English text of a draft of this manuscript. The project was funded by the National Key R&D Program of China (2017YFA0504700), the National Natural Science Foundation of China (31930069), the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB37040101), and the Key Research Program of Frontier Sciences at the Chinese Academy of Sciences (ZDBS-LY- SM003), X. Zhang received scholarships from the ‘National Thousand (Young) Talents Program’ from the Office of Global Experts Recruitment in China.

More Information

Corresponding author: xzzhang@ibp.ac.cn (X. Zhang)
Received Date: 23 January 2021
Accepted Date: 13 February 2021

Available Online: 17 May 2021

Publish Date: 28 February 2021

Abstract

Abstract

The frequency-dependent signal to noise ratio of cryo-electron microscopy data varies dramatically with the frequency and with the type of the data. During different steps of data processing, data with distinct SNR are used for calculations. Thus, specific weighting function based on the particular SNR should be designed to optimize the corresponding calculation. Here, we deduced these weighting functions by maximizing the signal to noise ratio of cross correlated coefficients. Some of our weighting functions for refinement resemble that used in the existing software packages. However, weighting functions we deduced for motion correction, particle picking and the refinement with overlapping densities differ from those employed by existing programs. Our new weighting functions may improve the calculation in these steps.
- Cryo-electron microscopy (Cryo-EM),
- Cross correlation coefficient (CCC),
- Weighting function

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References(17)

References

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