Transmembrane protein 70 (TMEM70)

Transmembrane protein 70 (TMEM70) is an inner mitochondrial membrane protein essential for the proper assembly and stabilization of mitochondrial ATP synthase (complex V), a key enzyme in the process of oxidative phosphorylation responsible for ATP production in eukaryotic cells[1][3][4][5][7]. TMEM70 acts as an ancillary assembly factor, particularly facilitating the formation and incorporation of the F1 and Fo subunits of ATP synthase[3][7]. Mutations in the TMEM70 gene cause mitochondrial complex V deficiency, primarily manifesting as neonatal mitochondrial encephalocardiomyopathy with symptoms such as hypotonia, severe lactic acidosis, hypertrophic cardiomyopathy, 3-methylglutaconic aciduria, and multi-organ failure[2][3][4][8]. The gene is nuclear-encoded, and TMEM70 deficiency is inherited in an autosomal recessive manner, with several pathogenic mutations—especially prevalent in certain populations—leading to severe metabolic disorders that are often fatal in early life[2][4][8]. TMEM70 is not a therapeutic target in the classical sense (receptor, enzyme, transporter), and there are no approved drugs acting on it or developed biomarkers for patient selection outside molecular genetic diagnostics. Key literature and databases consistently describe TMEM70 as an essential mitochondrial transmembrane assembly factor with a critical structural and biogenetic role, but not as a pharmacologically actionable target suitable for direct therapeutic intervention[2][4][7].

Other names

MC5DN2FLJ20533mitochondrial complex V deficiency nuclear type 1mitochondrial complex V deficiency, nuclear type 1transmembrane protein 70, mitochondrial