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bioRxiv · 10.1101/2021.04.08.438956

Volumetric morphometry reveals mitotic spindle width as the best predictor of spindle scaling

Kletter, T.·Reusch, S.·Dempewolf, N.·Tischer, C.·Reber, S.
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Abstract

The function of cellular structures at the mesoscale is dependent on their geometry and proportionality to cell size. The mitotic spindle is a good example why length and shape of intracellular organelles matter. Spindle length determines the distance over which chromosomes will segregate and spindle shape ensures bipolarity. While we still lack a systematic and quantitative understanding of subcellular morphometrics, new imaging techniques and volumetric data analysis promise novel insights into scaling relations across different species. Here, we introduce Spindle3D, an open-source plug-in that allows for the quantitative, unbiased, and automated analysis of 3D fluorescent data of spindles and chromatin. We systematically analyse different cell types, including somatic cells, stem cells and one-cell embryos across different phyla to derive volumetric relations of spindle, chromatin, and cell volume. Taken together, our data indicate that mitotic spindle width is a robust indicator of spindle volume, which correlates linearly with chromatin and cell volume both within single cell types and across metazoan phyla.

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Kletter, T., Reusch, S., Dempewolf, N., Tischer, C., Reber, S.. 2021-04-08. Volumetric morphometry reveals mitotic spindle width as the best predictor of spindle scaling. https://doi.org/10.1101/2021.04.08.438956

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