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This version (2021/02/12 11:29) was approved by shaikh.The Previously approved version (2021/02/12 11:22) is available.Diff

Signal subtraction

What do I need?

This protocol assumes that you have run Meridien.


Average and Filter
Average and low-pass filter a map for segmentation.
Segment Filtered Map
Display the map in Chimera, and locate regions to be subtracted.
Generate and Apply Mask
Make a soft mask of the region to be excluded.
Project and Subtract
Compute re-projections of map to be subtracted, and subtract them from the original images.
Compute 3D Reconstruction
Compute a 3D reconstruction using refinement iteration used for signal-subtraction.
Center Map
Center map of remaining density.

What do I do next?

Once these steps have been completed, perform a restricted refinement.

Author / Maintainer

Tapu Shaikh

Based on protocol developed by Zhong Huang and Pawel Penczek


Bai XC, Yan C, Yang G, Lu P, Ma D, Sun L, Zhou R, Scheres SHW, Shi Y. (2015) “An atomic structure of human γ-secretase.” Nature 525: 212-217. doi: 10.1038/nature14892.

pipeline/subtract/start.txt · Last modified: 2021/02/12 11:29 by shaikh