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Updated: Jul 17, 2026

Phosphorus-31 Magnetic Resonance Spectroscopy: A Tool for Measuring In Vivo Mitochondrial Oxidative Phosphorylation Capacity in Human Skeletal Muscle
09:40

Phosphorus-31 Magnetic Resonance Spectroscopy: A Tool for Measuring In Vivo Mitochondrial Oxidative Phosphorylation Capacity in Human Skeletal Muscle

Published on: January 19, 2017

Mitochondrial phosphate-carrier deficiency: a novel disorder of oxidative phosphorylation

Johannes A Mayr1, Olaf Merkel, Sepp D Kohlwein

  • 1Department of Pediatrics, Paracelsus Private Medical University, Salzburg, Austria. h.mayr@salk.at

American Journal of Human Genetics
|February 3, 2007
PubMed

Insights

Mitochondrial phosphate carrier deficiency, caused by a SLC25A3 gene mutation, impairs ATP synthesis. This genetic defect leads to severe infant health issues, including lactic acidosis and cardiomyopathy.

Area of Science:

  • Biochemistry
  • Genetics
  • Cell Biology

Background:

  • The mitochondrial phosphate carrier (SLC25A3) is crucial for ATP production.
  • Inorganic phosphate transport into mitochondria fuels aerobic energy synthesis.

Observation:

  • Two infants presented with lactic acidosis, hypertrophic cardiomyopathy, and hypotonia.
  • A homozygous mutation (c.215G-->A) in SLC25A3 exon 3A was identified.

Findings:

  • Mitochondrial studies revealed impaired ATP synthesis in muscle tissue.
  • This defect correlated with tissue-specific alternative splicing of SLC25A3.
  • Complementation analysis in yeast confirmed the enzyme deficiency.

Implications:

  • This study reports the first human patients with mitochondrial phosphate carrier deficiency.
  • The findings highlight the critical role of SLC25A3 in human health.
  • Understanding this deficiency may inform future diagnostics and therapies.

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