Catalyzes the transport of 2-oxoglutarate (alpha-oxoglutarate) across the inner mitochondrial membrane in an electroneutral exchange for malate. Can also exchange 2-oxoglutarate for other dicarboxylic acids such as malonate, succinate, maleate and oxaloacetate, although with lower affinity. Contributes to several metabolic processes, including the malate-aspartate shuttle, the oxoglutarate/isocitrate shuttle, in gluconeogenesis from lactate, and in nitrogen metabolism (By similarity). Maintains mitochondrial fusion and fission events, and the organization and morphology of cristae (PubMed:21448454). Regulator of apoptosis, insulin secretion and germline proliferation (PubMed:21448454). Furthermore, plays a role in the oxidative stress response regulating endogenous levels of reactive oxygen species (ROS) (PubMed:21884719). Involved in the regulation of lin-35/Rb-mediated apoptosis in the germline (PubMed:21448454). (S)-malate(in) + 2-oxoglutarate(out) = (S)-malate(out) + 2-oxoglutarate(in) 2-oxoglutarate(out) + malonate(in) = 2-oxoglutarate(in) + malonate(out) 2-oxoglutarate(out) + succinate(in) = 2-oxoglutarate(in) + succinate(out) 2-oxoglutarate(out) + maleate(in) = 2-oxoglutarate(in) + maleate(out) 2-oxoglutarate(out) + oxaloacetate(in) = 2-oxoglutarate(in) + oxaloacetate(out) Interacts with ant-1.1 and ced-9. Ubiquitously expressed, but highly expressed in the anterior pharynx. First expressed in intestinal precursor cells during embryogenesis. Expressed in intestinal and neuronal cells in newly hatched larvae at the L1 stage of development. Viable, with no visible phenotype (PubMed:21884719). Animals have increased levels of reactive oxygen species along with increased sensitivity to the reactive oxygen species (ROS) generator Jugalone (5-hydroxy-1,4-naphtoquinone) (PubMed:21884719). Conversely, display increased resistance to sodium azide, which is a mitochondrial poison that inhibits cytochrome c (PubMed:21884719). Animals also have morphological defects in their mitochondondria, whereby mitochondria are smaller in size, abnormally shaped, and contain fewer cristae which are irregular and disorganized (PubMed:21448454). Increased germline apoptosis characterized by an increased number of apoptotic corpses in the gonadal arms (PubMed:21448454). RNAi-mediated knockdown results in increased secretion of a beta-type insulin, daf-28 by coelomocytes and longer distal tip processes (PubMed:21448454). Belongs to the mitochondrial carrier (TC 2.A.29) family.