Mpc2 is a subunit of the mitochondrial pyruvate carrier (MPC) hetero-oligomeric complex, along with Mpc1. The MPC complex is crucial as it transports pyruvate, a product of glycolysis in the cytosol, across the inner mitochondrial membrane into the mitochondrial matrix. This process links cytosolic and mitochondrial metabolism, being essential for processes like the tricarboxylic acid cycle, generation of reducing equivalents and ATP, and biosynthesis of glucose, fatty acids, and amino acids [2,3,4].

Genetic ablation of Mpc2 has shown significant impacts. In adult murine hearts, genetic ablation of the MPC (including Mpc2) was sufficient to induce hypertrophy and heart failure, indicating its importance in cardiac function [1]. In hepatocyte-specific Mpc2 knockout (LS-Mpc2-/-) mice, there was reduced phosphorylation of the rate-limiting enzyme in branched chain amino acid (BCAA) catabolism, along with activation of mTOR signaling, demonstrating a role in BCAA metabolism [5]. In mice, genetic inactivation of Mpc2 led to basal cell hyperplasia in the tracheal epithelium, reduced ciliated cells during homeostasis, and delayed epithelial regeneration following injury, highlighting its role in airway basal progenitor cell function [7]. In addition, knockdown of Mpc2 in cultured HK2 cells exacerbated cisplatin-induced acute kidney injury, while overexpression attenuated the nephrotoxicity, showing its significance in kidney protection [6].

In conclusion, Mpc2 plays essential roles in multiple biological processes. Through gene knockout studies in mouse models, it has been revealed to be crucial in cardiac function, BCAA metabolism, airway basal progenitor cell function, and kidney protection. Understanding Mpc2's function provides insights into the pathogenesis of related diseases such as heart failure, metabolic disorders, and airway and kidney diseases, potentially guiding the development of new therapeutic strategies.