Whole-organism 3D Quantitative Characterization of Zebrafish Melanin by Silver Deposition Micro-CT

Katz, S. R.; Yakovlev, M. A.; Vanselow, D. J.; Ding, Y.; Lin, A. Y.; Parkinson, D. Y.; Wang, Y.; Canfield, V. A.; Ang, K. C.; Cheng, K. C.

doi:10.1101/2021.03.11.434673

bioRxiv · 10.1101/2021.03.11.434673

Whole-organism 3D Quantitative Characterization of Zebrafish Melanin by Silver Deposition Micro-CT

Katz, S. R.·Yakovlev, M. A.·Vanselow, D. J.·Ding, Y.·Lin, A. Y.·Parkinson, D. Y.·Wang, Y.·Canfield, V. A.·Ang, K. C.·Cheng, K. C.

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Abstract

Melanin-rich zebrafish melanophores are used to study pigment development, human skin color, and as a large-scale screening phenotype. To facilitate more detailed whole-body, computational analyses of melanin content and morphology, we have combined X-ray microtomography (micro-CT), a non-destructive, full-volume imaging modality, with a novel application of ionic silver staining to characterize melanin distribution in whole zebrafish larvae. Normalized micro-CT reconstructions of silver-stained fish consistently reproduced pigment patterns seen by light microscopy, and allowed direct quantitative comparisons of melanin content across wild-type and mutant samples, for both dramatic and subtle phenotypes not previously described. Silver staining of melanin for micro-CT provides proof-of-principle for whole-body, three-dimensional computational phenomic analysis of a particular cell type at cellular resolution, with potential applications in other model organisms and human melanoma biopsies. Whole-organism, high-resolution phenotyping is a challenging ideal, but provides superior context for functional studies of mutations, diseases, and environmental influences.

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Katz, S. R., Yakovlev, M. A., Vanselow, D. J., Ding, Y., Lin, A. Y., Parkinson, D. Y., Wang, Y., Canfield, V. A., Ang, K. C., Cheng, K. C.. 2021-03-12. Whole-organism 3D Quantitative Characterization of Zebrafish Melanin by Silver Deposition Micro-CT. https://doi.org/10.1101/2021.03.11.434673

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