Javier García Varo (Karlsruhe Institute of Technology, KIT)
Javier García Varo's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at Karlsruhe Institute of Technology in the year 2024 with the title:
Functional characterization of the terpene synthase ZmTPS2 in TBY-2 cells
This thesis attempted to elucidate the potential role of stromulation during in secondary metabolism by using the terpenoid synthesis pathway as a case study in the model system tobacco BY-2 cell culture.
Crosstalk between metabolic processes in cellular compartments enables cells to integrate signals and exchange metabolites, which is crucial for the regulation and production of vital compounds, as in the case of terpenes where multiple compartments are involved during the biosynthesis process.
To explore if stromules act as a metabolic conduit in terpene synthesis between compartments the generation of transgenic BY-2 cells overexpressing fluorescently labelled variants of the terpene synthase ZmTPS2 from maize was attempted. Furthermore, the subcellular location of terpenoid precursors was explored by performing a qualitative and quantitative colocalization analysis of synthetic, fluorescent analogues with the help of organelle dyes or fluorescent markers.
The transgene was successfully integrated into the TBY-2 genome but did not show transcriptional activity and microscopic analysis was not possible. Colocalization of the fluorescent compounds show a strong overlapping signal in lipophilic environments like lipid droplets but low overlap in ER which was altered after treatment with Brefeldin A an inhibitor of protein transport. No overlap in peroxisomes was visible. In addition, the motility of precursors were explored through inhibiting actin-myosin movement showing independent movement of the fluorescent compound in the cell. Lastly, stromule frequency was altered during metabolic inhibition of MEP-pathway.
Therefore, this study may provide the fundament for further research about the connection of metabolic processes by organelle shape and hints at new functional aspects of stromulation.
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Javier García Varo conducted this work at the Joseph-Gottlieb Kölreuter Institute for Plant Sciences (JKIP) in the working group of Prof. Peter Nick.
