Mitochondrial protein enriched in neurons that acts as a regulator of mitochondrial respiration (PubMed:30318146). Associates with the ATP synthase complex and facilitates ATP synthesis (PubMed:30318146). May be a chaperone protein involved in the turnover of the subunits of mitochondrial complex I N-module. It facilitates the degradation of N-module subunits damaged by oxidative stress, and contributes to complex I functional efficiency (By similarity). Associates with the ATP synthase complex. Interacts with MT-ATP6; interaction is direct. Interacts with ATP5MC2; interaction is direct. In brain, expressed in gray matter structures. Mice are smaller and have a decreased weight (PubMed:30318146). Neocortical projection neurons display morphological defects reminiscent of Williams-Beuren syndrome (WBS) in human, characterized by less complex dendritic architecture and a smaller corpus callosum (PubMed:30318146). Mitochondria show decreased ATP production (PubMed:30318146). Mice do not show significant systemic metabolic defects (PubMed:30318146).