Disorders of ATP synthase, the key enzyme in mitochondrial energy supply, belong to the most severe metabolic diseases, manifesting as early-onset mitochondrial encephalo-cardiomyopathies. Since ATP synthase subunits are encoded by both mitochondrial and nuclear DNA, pathogenic variants can be found in either genome. In addition, the biogenesis of ATP synthase requires several assembly factors, some of which are also hotspots for pathogenic variants. While variants of MT-ATP6 and TMEM70 represent the most common cases of mitochondrial and nuclear DNA mutations respectively, the advent of next-generation sequencing has revealed new pathogenic variants in a number of structural genes and TMEM70, sometimes with truly peculiar genetics. Here we present a systematic review of the reported cases and discuss biochemical mechanisms, through which they are affecting ATP synthase. We explore how the knowledge of pathophysiology can improve our understanding of enzyme biogenesis and function. Keywords: Mitochondrial diseases o ATP synthase o Nuclear DNA o Mitochondrial DNA o TMEM70.

• MeSH
• fenotyp * MeSH
• lidé MeSH
• membránové proteiny genetika   metabolismus   MeSH
• mitochondriální DNA genetika   MeSH
• mitochondriální nemoci genetika   enzymologie   MeSH
• mitochondriální proteiny genetika   metabolismus   MeSH
• mitochondriální protonové ATPasy * genetika   metabolismus   MeSH
• mitochondrie enzymologie   genetika   MeSH
• mutace MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• systematický přehled MeSH
• Názvy látek
• membránové proteiny MeSH
• mitochondriální DNA MeSH
• mitochondriální proteiny MeSH
• mitochondriální protonové ATPasy * MeSH
• TMEM70 protein, human MeSH Prohlížeč

Mutations of the TMEM70 gene disrupt the biogenesis of the ATP synthase and represent the most frequent cause of autosomal recessive encephalo-cardio-myopathy with neonatal onset. Patient tissues show isolated defects in the ATP synthase, leading to the impaired mitochondrial synthesis of ATP and insufficient energy provision. In the current study, we tested the efficiency of gene complementation by using a transgenic rescue approach in spontaneously hypertensive rats with the targeted Tmem70 gene (SHR-Tmem70ko/ko), which leads to embryonic lethality. We generated SHR-Tmem70ko/ko knockout rats expressing the Tmem70 wild-type transgene (SHR-Tmem70ko/ko,tg/tg) under the control of the EF-1α universal promoter. Transgenic rescue resulted in viable animals that showed the variable expression of the Tmem70 transgene across the range of tissues and only minor differences in terms of the growth parameters. The TMEM70 protein was restored to 16-49% of the controls in the liver and heart, which was sufficient for the full biochemical complementation of ATP synthase biogenesis as well as for mitochondrial energetic function in the liver. In the heart, we observed partial biochemical complementation, especially in SHR-Tmem70ko/ko,tg/0 hemizygotes. As a result, this led to a minor impairment in left ventricle function. Overall, the transgenic rescue of Tmem70 in SHR-Tmem70ko/ko knockout rats resulted in the efficient complementation of ATP synthase deficiency and thus in the successful genetic treatment of an otherwise fatal mitochondrial disorder.

• Klíčová slova
• ATP synthase deficiency, TMEM70 factor, gene therapy, mitochondria disease, transgenic rescue,
• Publikační typ
• časopisecké články MeSH