Endosymbiosis, metabolite transport, chloroplast envelope membrane, C4 photosynthesis, transcriptomics, evolution
Exchange of metabolites between plastids and cytosol is crucial for the integration of plastids into the metabolic network of plant cells. However, despite the importance for understanding the processes involved in establishing plastids through endosymbiosis and for the function of photosynthetic eukaryotic cells, still remarkably little is known about the genes encoding metabolite transporters that connect the plastid with the cytosol. Here we provide an update on the building blocks and gaps of current knowledge about chloro-plast solute transporters in extant plastids of the green lineage. We also describe a novel and promising approach to identify a transporters at the molecular level and describe its functional characterization. Specifically, we highlight the potential of comparative transcriptomic analysis of C3 and C4 plant species for identifying novel transporters.