Protein Interaction Patterns in Arabidopsis thaliana Leaf Mitochondria Change in Response to Illumination

Mitochondrial biology is underpinned by the presence and activity of large protein complexes participating in the organelle-located parts of cellular respiration, the TCA cycle and oxidative phosphorylation. While the enzymatic roles of these complexes are undisputed, little is known about the interactions of the subunits beyond their presence in the monomeric protein complexes and their functions in regulating mitochondria metabolism. By applying one of the most important regulatory cues for plant metabolism, the presence or absence of light, we here assess the changes in the composition and molecular mass of known mitochondrial protein complexes by employing a differential complexome profiling strategy. Covering a mass range up to 25 MDa, we demonstrate dynamic associations of TCA-cycle enzymes and of OXPHOS components. The data presented here form the basis for future studies aiming to advance our understanding of the role of protein:protein interactions in the regulation of plant mitochondrial functions.