The Oxidative Phosphorylation system of the mitochondria in plants

Highlights

• Oxidative phosphorylation (OXPHOS) and photosynthesis are interdependent in plants.

• OXPHOS modes vary along the daily light–dark cycle and diverse stress responses.

• The mitochondrial electron transfer chain (ETC) is branched and multifunctional.

• ETC complexes harbor extra functions in plants.

Abstract

Mitochondrial Oxidative Phosphorylation (OXPHOS) provides ATP for driving cellular functions. In plants, OXPHOS takes place in the context of photosynthesis. Indeed, metabolism of mitochondria and chloroplasts is tightly linked. OXPHOS has several extra functions in plants. This review takes a view on the OXPHOS system of plants, the electron transfer chain (ETC), the ATP synthase complex and the numerous supplementary enzymes involved. Electron transport pathways are especially branched in plants. Furthermore, the “classical” OXPHOS complexes include extra subunits, some of which introduce side activities into these complexes. Consequently, and to a remarkable degree, OXPHOS is a multi-functional system in plants that needs to be efficiently regulated with respect to all its physiological tasks in the mitochondria, the chloroplasts, and beyond. Regulatory mechanisms based on posttranslational protein modifications and formation of supramolecular protein assemblies are summarized and discussed.