Methylglyoxal-mediated Gpd1 activation restores the mitochondrial defects in a yeast model of mitochondrial DNA depletion syndrome.
Biochim Biophys Acta Gen Subj
; 1867(5): 130328, 2023 05.
Article
in En
| MEDLINE
| ID: mdl-36791826
ABSTRACT
Human MPV17, an evolutionarily conserved mitochondrial inner-membrane channel protein, accounts for the tissue-specific mitochondrial DNA depletion syndrome. However, the precise molecular function of the MPV17 protein is still elusive. Previous studies showed that the mitochondrial morphology and cristae organization are severely disrupted in the MPV17 knockout cells from yeast, zebrafish, and mammalian tissues. As mitochondrial cristae morphology is strictly regulated by the membrane phospholipids composition, we measured mitochondrial membrane phospholipids (PLs) levels in yeast Saccharomyces cerevisiae MPV17 ortholog, SYM1 (Stress-inducible Yeast MPV17) deleted cells. We found that Sym1 knockout decreases the mitochondrial membrane PL, phosphatidyl ethanolamine (PE), and inhibits respiratory growth at 37 ÌC on rich media. Both the oxygen consumption rate and the steady state expressions of mitochondrial complex II and super-complexes are compromised. Apart from mitochondrial PE defect a significant depletion of mitochondrial phosphatidyl-choline (PC) was noticed in the sym1∆ cells grown on synthetic media at both 30 ÌC and 37 ÌC temperatures. Surprisingly, exogenous supplementation of methylglyoxal (MG), an intrinsic side product of glycolysis, rescues the respiratory growth of Sym1 deficient yeast cells. Using a combination of molecular biology and lipid biochemistry, we uncovered that MG simultaneously restores both the mitochondrial PE/PC levels and the respiration by enhancing cytosolic NAD-dependent glycerol-3-phosphate dehydrogenase 1 (Gpd1) enzymatic activity. Further, MG is incapable to restore respiratory growth of the sym1∆gpd1∆ double knockout cells. Thus, our work provides Gpd1 activation as a novel strategy for combating Sym1 deficiency and PC/PE defects.
Key words
Full text:
1
Database:
MEDLINE
Main subject:
Saccharomyces cerevisiae
/
Saccharomyces cerevisiae Proteins
Language:
En
Journal:
Biochim Biophys Acta Gen Subj
Year:
2023
Type:
Article
Affiliation country:
India