Mitochondrial respiratory dysfunction-elicited oxidative stress and posttranslational protein modification in mitochondrial diseases.
Pathogenic mutation in mtDNA and mitochondrial dysfunction are associated with mitochondrial diseases. In this review, we discuss the oxidative stress-elicited mitochondrial protein modifications that may contribute to the pathophysiology of mitochondrial diseases. We demonstrated that excess ROS produced by defective mitochondria could increase the acetylation of microtubule proteins through the suppression of Sirt2, which results in perinuclear distribution of mitochondria in skin fibroblasts of patients with CPEO syndrome. Our recent work showed that mitochondrial dysfunction-induced oxidative stress can disrupt protein degradation system by inhibiting the ubiquitin-proteasome pathway and protease activity in human cells harboring mutant mtDNA. This in turn causes accumulation of aberrant proteins in mitochondria and renders the mutant cells more susceptible to apoptosis induced by oxidative stress. Furthermore, oxidative stress can modulate phosphorylation of mitochondrial proteins, which can affect metabolism in a number of diseases. Taken together, we suggest that oxidative stress-triggered protein modifications and defects in protein turnover play an important role in the pathogenesis and progression of mitochondrial diseases.
Wu
Yu-Ting
YT
Department of Biochemistry and Molecular Biology, School of Life Sciences, National Yang-Ming University, Taipei, Taiwan.
Wu
Shi-Bei
SB
Lee
Wan-Yu
WY
Wei
Yau-Huei
YH
D000107:Acetylation; D000818:Animals; D004272:DNA, Mitochondrial / Q000378:metabolism; D018450:Disease Progression; D004579:Electron Transport; D006801:Humans; D008239:Lysine / Q000737:chemistry; D008928:Mitochondria / Q000378:metabolism* / Q000473:pathology*; D028361:Mitochondrial Diseases / Q000378:metabolism* / Q000473:pathology; D009154:Mutation; D018384:Oxidative Stress; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D013577:Syndrome; D025801:Ubiquitin / Q000737:chemistry
D004272:DNA, Mitochondrial; D025801:Ubiquitin; D008239:Lysine