Mitochondrial adenylate carrier that catalyzes specifically the transport of ATP, ADP and AMP by a counter-exchange mechanism across the inner mitochondrial membrane. Substrate preference in reconstituted proteoliposomes is ATP > AMP > ADP. May play a role in oxidative phosphorylation and be important for the provision of energy required to support growth in heterotrophic tissues. Inhibited by pyridoxal 5-phosphate, bathophenanthroline, mersalyl, p-hydroxymercuribenzoate and tannic acid. A number of isoforms are produced. According to EST sequences. Expressed in seedling radicles and roots, vasculature of cotyledons, leaf primordia, leaves and sepals. Reduced root growth and respiration. Belongs to the mitochondrial carrier (TC 2.A.29) family.