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Genetic Ablation of Sfxn5 Induces Mitochondrial Dysfunction and Precipitates Lethal Metabolic Crisis in Mice

ABSTRACT: Mitochondrial disorders frequently manifest with life-threatening hepatic metabolic crises. Using a global Sfxn5-knockout mouse model, we investigated the systemic consequences of disrupting this mitochondrial inner-membrane transporter through integrated biochemical, metabolomic, histological, and ultrastructural analyses. Sfxn5 deficiency resulted in complete postnatal lethality accompanied by severe metabolic collapse and progressive multi-organ dysfunction. The liver emerged as the primary site of pathology, exhibiting marked mitochondrial structural damage and widespread disruption of central metabolic pathways, including the tricarboxylic acid cycle, fatty acid β-oxidation, and ammonia detoxification, leading to hyperammonemia and systemic metabolic stress. Importantly, liver-specific reconstitution of Sfxn5 partially restored mitochondrial metabolic function, substantially reduced hyperammonemia, and alleviated multi-organ pathology. Altogether, these findings identify hepatic mitochondrial dysfunction as the central driver of Sfxn5-dependent lethality and establish a critical role for Sfxn5 in maintaining mitochondrial metabolic homeostasis during early postnatal life.

INSTRUMENT(S): Liquid Chromatography MS - negative - reverse-phase, Liquid Chromatography MS - positive - reverse-phase

PROVIDER: MTBLS14628 | MetaboLights | 2026-05-30

REPOSITORIES: MetaboLights

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			Action	DRS
	a_MTBLS14628_LC-MS_negative_reverse-phase.txt	Txt
	a_MTBLS14628_LC-MS_positive_reverse-phase.txt	Txt
	i_Investigation.txt	Txt
	m_MTBLS14628_LC-MS_negative_reverse-phase_v2_maf.tsv	Tabular
	m_MTBLS14628_LC-MS_positive_reverse-phase_v2_maf.tsv	Tabular

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Genetic Ablation of Sfxn5 Induces Mitochondrial Dysfunction and Precipitates Lethal Metabolic Crisis in Mice

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