# Proteomic atlas of Paramecium bursaria shows lipid droplet remodeling around symbiotic algae

- Published: 2026-11-07 18:18 UTC
- Section: Life & Health › Biology & biochemistry
- Tags: Paramecium bursaria, spatial proteomics, endosymbiosis, perialgal vacuole, lipid droplets, green algae, mass spectrometry, lipid metabolism inhibitors, ciliate
- URL: https://realtech.media/news/rt-801e5c603c55bc9ed679e54b_proteomic_atlas_of/

**Mass spectrometry mapped proteins in the ciliate with and without algal endosymbionts; lipid droplets changed and gathered near algae, and inhibiting lipid metabolism cut algal numbers.**

![Proteomic atlas of Paramecium bursaria shows lipid droplet remodeling around symbiotic algae](https://realtech.media/media/2026/11/b9810b37932e4788.jpg)
*Fritzmann2002, Wikimedia Commons, CC BY-SA 4.0*

Researchers reported in Science Advances a spatial proteomic atlas of the ciliate Paramecium bursaria, built with mass spectrometry-based proteomics. The atlas compares host cells with and without endosymbiotic green algae. [1] P. bursaria and its algae are a model system for studying the early evolution of endosymbiosis, but how the host maintains the relationship has remained unclear. [1]

The atlas defines the protein composition of the perialgal vacuole, the compartment that contains the endosymbiont. It also shows pronounced remodeling of host lipid droplets in symbiosis. [1] Imaging analyses confirmed that the droplets change in size, morphology and positioning, and accumulate near intracellular algae. [1]

When the authors treated symbiotic cells with chemical inhibitors of lipid metabolism, the number of endosymbiotic algae decreased. According to the authors, this indicates a role for lipid droplets in the host-endosymbiont interaction. [1] They also describe the dataset as a resource for protein localization in P. bursaria cells and as an account of how the cells remodel an existing compartment to maintain endosymbiosis.

## Sources

1. [Science Advances](https://doi.org/10.1126/sciadv.aeg5123)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-801e5c603c55bc9ed679e54b_proteomic_atlas_of/