ZFIN ID: ZDB-PUB-200423-2
Methylmalonyl acidemia: from mitochondrial metabolism to defective mitophagy and disease
Luciani, A., Devuyst, O.
Date: 2020
Source: Autophagy : 1-3 (Other)
Registered Authors: Devuyst, Oliver, Luciani, Alessandro
Keywords: Cell damage, inherited metabolic disorders, kidney tubule, metabolism, mitochondria, mitophagy, oxidative stress
MeSH Terms:
  • Animals
  • Autophagy
  • Methylmalonyl-CoA Mutase
  • Mitochondria
  • Mitophagy*
  • Ubiquitin-Protein Ligases
  • Zebrafish*
PubMed: 32316822 Full text @ Autophagy
Methylmalonic acidemia (MMA) is an autosomal recessive inborn error of metabolism due to the deficiency of mitochondrial MMUT (methylmalonyl-CoA mutase) - an enzyme that mediates the cellular breakdown of certain amino acids and lipids. The loss of MMUT leads to the accumulation of toxic organic acids causing severe organ dysfunctions and life-threatening complications. The mechanisms linking MMUT deficiency, mitochondrial alterations and cell toxicity remain uncharacterized. Using cell and animal-based models, we recently unveiled that MMUT deficiency impedes the PINK1-induced translocation of PRKN/Parkin to MMA-damaged mitochondria, thereby halting their delivery and subsequent degradation by macroautophagy/autophagy-lysosome systems. In turn, this defective mitophagy process instigates the accumulation of dysfunctional mitochondria that spark epithelial distress and tissue damage. Correction of PINK1-directed mitophagy defects or mitochondrial dysfunctions rescues epithelial distress in MMA cells and alleviates disease-relevant phenotypes in mmut‒deficient zebrafish. Our findings suggest a link between primary MMUT deficiency and diseased mitochondria, mitophagy dysfunction and cell distress, offering potential therapeutic perspectives for MMA and other metabolic diseases.