A loss-of-function mutation in the GTPase domain of MFN2, perverting mitochondrial dynamics, is associated with dilated cardiomyopathy

Verdict. Molecular docking further showed a weakened interaction between MFN2-N311S and PRKN (Parkin), indicating impaired mitophagy and defective mitochondrial quality control. It intersects mitochondrial stress/dysfunction themes (functional impairment; molecular/genetic defect; reactive oxygen species).

What the authors report

Mitofusin 2 (MFN2), a key outer mitochondrial membrane GTPase, regulates mitochondrial fusion, mitophagy, calcium homeostasis, and cellular bioenergetics. This study investigated the role of MFN2 variants in patients with Dilated Cardiomyopathy (DCM) using whole-exome sequencing (WES) of 5 familial and 10 sporadic DCM cases.

Key results stated in the abstract include the following. Molecular docking further showed a weakened interaction between MFN2-N311S and PRKN (Parkin), indicating impaired mitophagy and defective mitochondrial quality control. Moreover, functional analysis in stable H9c2 cardiomyoblast cell lines demonstrated significantly reduced MFN2 mutant protein expression, extensive mitochondrial clustering and fragmentation. The mutant protein also indicated significant reduction in mitochondrial membrane potential, ATP production, and oxygen consumption rate (OCR), together with elevated cytosolic Ca2+ and reactive oxygen species (ROS) levels. qRT-PCR analysis further revealed activation of the PI3K/AKT/mTOR signalling pathway and increased expression of hypertrophic markers Myh6, Nppa, Nfatc1, and Nfatc2.

Why it matters for mitochondrial biology

Within mitochondrial research, this work maps primarily to mitophagy, mitochondrial dynamics, calcium signaling, redox biology. It is relevant to mitochondrial dysfunction discourse because the abstract invokes functional impairment, molecular/genetic defect, reactive oxygen species, mitophagy. That does not by itself establish a validated disease mechanism; it indicates thematic proximity. Because a therapeutic or interventional angle is present, the piece is of interest for mitochondrial-targeted drug hypothesis generation—subject to full-text validation of endpoints and safety context. Server: medrxiv. Posted 2026-08-11. Synthesis confidence is bounded by abstract completeness.

Study design (abstract-level)

This study investigated the role of MFN2 variants in patients with Dilated Cardiomyopathy (DCM) using whole-exome sequencing (WES) of 5 familial and 10 sporadic DCM cases. N311S), was identified in a DCM patient, which is absent in 100 healthy controls as well as in the 1000 Genomes, IndiGenomes, databases while it shows very low MAF (0.0000081) in gnomAD. Structural modelling predicted the variant to be highly deleterious and revealed marked conformational distortion of the mutant protein (RMSD = 8.95 A).

Principal findings

1. Molecular docking further showed a weakened interaction between MFN2-N311S and PRKN (Parkin), indicating impaired mitophagy and defective mitochondrial quality control.
2. Moreover, functional analysis in stable H9c2 cardiomyoblast cell lines demonstrated significantly reduced MFN2 mutant protein expression, extensive mitochondrial clustering and fragmentation.
3. The mutant protein also indicated significant reduction in mitochondrial membrane potential, ATP production, and oxygen consumption rate (OCR), together with elevated cytosolic Ca2+ and reactive oxygen species (ROS) levels. qRT-PCR analysis further revealed activation of the PI3K/AKT/mTOR signalling pathway and increased expression of hypertrophic markers Myh6, Nppa, Nfatc1, and Nfatc2.
4. The above findings collectively highlight the significant impact of the MFN2 mutation on mitochondrial dynamics and cellular health, suggesting a significant correlation with the pathogenesis of DCM.
5. This finding could further open a door to develop a potential therapeutic target for DCM.

Limitations of this brief

• This Mitos brief is an abstract-level synthesis of a preprint; it is not peer review and not a substitute for reading the full paper.
• Preprint status: findings may change with revision or journal review.
• Effect sizes, n numbers, statistics, and full experimental controls are typically incomplete at abstract resolution.
• Primary source: medrxiv DOI 10.64898/2026.08.10.26360061 (posted 2026-08-11).

Open scientific questions

• Which specific experimental panels in the full paper establish the strongest causal claim, and how robust are the controls?
• What dose, timing, and off-target profile would be required to take the intervention seriously as a therapeutic hypothesis?
• Does the work distinguish mitophagy flux from static marker changes (e.g., LC3, PINK1/Parkin pathway activity)?
• How do these findings sit relative to prior literature on the same pathway—replication, contradiction, or incremental extension?

Bottom line

For mitochondrial biologists focused on mitophagy, mitochondrial dynamics, calcium signaling, this preprint is worth full-text review soon. Abstract-level takeaway: Molecular docking further showed a weakened interaction between MFN2-N311S and PRKN (Parkin), indicating impaired mitophagy and defective mitochondrial quality control. Confirm methods, effect sizes, and controls in the full PDF before citing the result as established.

Bibliographic record

Abstract-based editorial synthesis by Mitos. Not peer review.