Elucidation of mitochondrial pyruvate transport and usage in Arabidopsis thaliana

This thesis highlights the extensive metabolic flexibility of plant mitochondria, focusing on the multiple layers that regulate pyruvate import and usage. Firstly, plants have multiple isoforms of the mitochondrial pyruvate carriers (MPCs) of which MPC1 is the most important. Secondly, there are three different metabolic pathways with different level of contribution to the mitochondrial pyruvate pool including pyruvate import via MPCs, internal production of pyruvate via NAD-malic enzyme and pyruvate shuffling between cytosol and mitochondria via alanine aminotransferases. Finally, plants control metabolic fluxes by substrate channelling-like events to prioritise the usage of imported pyruvate for respiration and ATP production.