MOTS-c (Mitochondrial Open reading frame of the Twelve S rRNA type-c) is a 16-amino-acid peptide encoded within the 12S ribosomal RNA region of mitochondrial DNA. It belongs to a small, growing class of mitochondrial-derived peptides (MDPs) that has reframed how researchers think about mitochondria — not only as metabolic organelles but as a source of signaling molecules. MOTS-c is used as a tool compound for studying mitochondrial-to-nuclear ("retrograde") signaling and cellular metabolic-pathway regulation.
A Mitochondrial-Encoded Signaling Peptide
MOTS-c was first characterized by Lee and colleagues in 2015. Unlike the vast majority of peptides, which are encoded in the nuclear genome, MOTS-c is translated from a short open reading frame within the mitochondrial genome. This unusual origin makes it a frequent reference compound in research on mtDNA-encoded regulatory peptides.
AMPK and the Folate–Methionine Cycle
Mechanistically, MOTS-c research centers on activation of AMP-activated protein kinase (AMPK), a central sensor of cellular energy state. In cell and rodent models, MOTS-c has been reported to modulate the folate–methionine cycle and purine biosynthesis, with downstream effects on AMPK signaling. Under conditions of metabolic stress, MOTS-c has been observed to translocate to the nucleus and influence stress-adaptive gene-expression programs, including antioxidant response elements — a core example of mitochondrial retrograde signaling.
Research Applications
- AMPK activation and substrate-handling studies
- Mitochondrial-to-nuclear (retrograde) signaling models
- Exercise-physiology and skeletal-muscle homeostasis models
- Age-related metabolic-pathway characterization
- Mitochondrial-derived-peptide (MDP) comparative pharmacology
References
- Lee C, Zeng J, Drew BG, et al. The mitochondrial-derived peptide MOTS-c promotes metabolic homeostasis and reduces obesity and insulin resistance. Cell Metab 2015. PMID: 25738459.
- Reynolds JC, Lai RW, et al. MOTS-c is an exercise-induced mitochondrial-encoded regulator of age-dependent physical decline and muscle homeostasis. Nat Commun 2021. PMID: 33473109.
This article summarizes publicly available research for educational purposes and does not constitute medical advice, a therapeutic claim, or a recommendation for human use. Products referenced are sold for laboratory research use only.