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bioRxiv · 10.64898/2026.10.13.758975

Subcellular spatial proteomics of the close animal relative, Capsaspora owczarzaki

Jirsova, D. G.·Poh, Y.-P.·Dabrowska, K.·Sharma, R.·Pirrotte, P.·Wideman, J. G.
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Abstract

Capsaspora owczarzaki is one of the closest relatives of animals and an increasingly tractable model for investigating the evolution of multicellularity. However, very little cell biological work has been done on the sister linages to animals. Subcellular spatial proteomics (SSP) is a technique that can localize thousands of proteins to subcellular compartments in a single experiment by combining cell fractionation with sensitive mass spectrometry. To provide broad insight into the localization of the Capsaspora proteome, we performed SSP based on a label-free version of LOPIT-DC (Localisation of Organelle Proteins by Isotope Tagging after Differential ultraCentrifugation). We detected 6,466 proteins, corresponding to 68.4% of the predicted Capsaspora proteome, and assigned high-confidence localizations to 3,106 of them across 13 subcellular compartments. This study serves as a proteomic dataset to resolve cellular compartmentalization in a close relative of animals, enabling downstream evolutionary, biological, and functional analyses. Investigators interested in using these data prior to publication are encouraged to contact us to avoid overlap and to facilitate coordinated and collaborative use of this resource.

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Jirsova, D. G., Poh, Y.-P., Dabrowska, K., Sharma, R., Pirrotte, P., Wideman, J. G.. 2026-10-15. Subcellular spatial proteomics of the close animal relative, Capsaspora owczarzaki. https://doi.org/10.64898/2026.10.13.758975

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