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bioRxiv · 10.1101/827006

Correction of missing-wedge artifacts in filamentous tomograms by template-based constrained deconvolution

Kovacs, J.·Song, J. H.·Auer, M.·He, J.·Wriggers, W. R.
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Abstract

Cryo-electron tomography maps often exhibit considerable noise and anisotropic resolution, due to the low-dose requirements and the missing wedge in Fourier space. These spurious features are visually unappealing and, more importantly, prevent an automated segmentation of geometric shapes, requiring a highly subjective, labor-intensive manual tracing. We developed a novel computational strategy for objectively denoising and correcting missing-wedge artifacts in the special but important case of repetitive basic shapes, such as filamentous structures. In this approach, we use the template and a non-negative "location map" to constrain the deconvolution scheme, allowing us to recover, to a considerable degree, the information lost in the missing wedge. We applied our method to data of actin-filament bundles of inner-ear stereocilia, which are critical in hearing transduction processes, and found a good overlap with the experimental map and with manual tracing. In addition, we demonstrate that our method can also be used for membrane detection.

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Kovacs, J., Song, J. H., Auer, M., He, J., Wriggers, W. R.. 2019-11-01. Correction of missing-wedge artifacts in filamentous tomograms by template-based constrained deconvolution. https://doi.org/10.1101/827006

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