Ivan GARCIA CUNCHILLOS, postdoctoral researcher of the Evolution and Genomics of Microbial Eukaryotes Research Team led by Prof. Anna KARNKOWSKA at the Institute of Evolutionary Biology (University of Warsaw) visited Gaëlle TOULLEC, postdoctoral researcher of the LPCV Photosymbiosis team and member of the AtlaSymbio project, at the Integrated Structure Biology platform in Grenoble (ISBG) last month.

This visit was an opportunity for Ivan and Gaëlle to work together on studying kleptoplasty phenomena within Rapaza viridis. Here are few words of Ivan regarding their research:

“Rapaza viridis is a marine, flagellate, unicellular species with mixotrophic capabilities. This species achieves mixotrophy through kleptoplasty, acquiring a chloroplast from a green chlorophyte algae (Tetraselmis sp.), and is the only known example of kleptoplasty in the phylum Euglenozoa. While the chloroplast remains temporarily functional inside the new host, multiple changes lead to its degradation, requiring constant replacements. In this collaboration, we aim to study the integration and subsequent modifications of the chloroplast in the new host using the cutting-edge technique of Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) to obtain a 3D reconstruction of this interaction. During the visit to the laboratory, we discussed the best alternatives to achieve these goals, combining the knowledge of both research teams on the species and the techniques. Consequently, we selected two points in the time series, from chloroplast acquisition to degradation, and preserved them using high-pressure cryofixation so that the samples retain the exact conditions. The results will provide us with a complete spatial and temporal picture of this interaction, as well as clues about the early and intermediate stages of plastid integration in the eukaryotic cell.”