What Is MOTS-c?
MOTS-c (Mitochondrial ORF of the 12S rRNA Type-c) is a 16-amino acid mitochondria-derived peptide (MDP) encoded not by the nuclear genome but by the mitochondrial genome itself — specifically within the 12S ribosomal RNA gene. First identified and characterised by Lee et al. in 2015 (Cell Metabolism), MOTS-c represents a class of bioactive peptides translated from small open reading frames (sORFs) within mitochondrial RNA, a discovery that fundamentally expanded understanding of mitochondrial biology.
Molecular Structure and Properties
- Sequence: MRWQEMGYIFYPRKLR
- Length: 16 amino acids
- Molecular weight: ~2,174 Da
- Origin: Encoded by mitochondrial 12S rRNA gene (mt-rRNA), translated by mitochondrial ribosomes
- Localisation: Cytoplasm and nucleus under metabolic stress conditions
- Supplied as: lyophilised powder for in vitro research use
Mechanism of Action: AMPK Activation and Metabolic Regulation
MOTS-c’s primary mechanism involves activation of AMPK (AMP-activated protein kinase), the master cellular energy sensor. Under conditions of metabolic stress — low ATP, glucose restriction, or exercise — MOTS-c translocates from mitochondria to the cytoplasm and nucleus, where it modulates gene expression and metabolic enzyme activity.
The proposed signalling pathway established in Lee et al. (2015):
- Folate cycle inhibition: MOTS-c interferes with the folate and methionine cycles, reducing the availability of 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) — a naturally occurring AMPK activator
- AMPK activation: The resulting AICAR accumulation (and direct AMPK activation) upregulates glucose uptake and fatty acid oxidation, and downregulates anabolic pathways consuming ATP
- Nuclear translocation and gene regulation: Under stress conditions, MOTS-c translocates to the nucleus, where it regulates adaptive nuclear gene expression — a process characterised by Kim et al. (2018) as a mitochondria-to-nucleus retrograde signalling pathway
Exercise Mimetic Properties
One of the most widely cited findings in MOTS-c research is its exercise mimetic activity. Reynolds et al. (2021, Nature Communications) demonstrated that circulating MOTS-c levels increase significantly during physical exercise in both mice and humans. In murine models, exogenous MOTS-c administration improved exercise performance, skeletal muscle glucose uptake, and insulin sensitivity — recapitulating aspects of the metabolic adaptations to exercise training at the molecular level.
This finding has positioned MOTS-c as a research tool for studying exercise-induced metabolic pathways in in vitro and preclinical models where direct exercise interventions are not feasible.
Insulin Sensitivity and Glucose Homeostasis
Lee et al. (2015) demonstrated that MOTS-c administration improved insulin sensitivity in diet-induced obese and age-induced insulin-resistant mouse models. Mechanistically, MOTS-c activated AMPK in skeletal muscle, promoting GLUT4 translocation and glucose uptake independent of insulin receptor signalling — a pathway of interest in research examining insulin resistance models.
Key Research Areas
Mitochondrial biology: MOTS-c is one of the first mitochondria-encoded peptides demonstrated to have systemic bioactivity, prompting re-evaluation of the mitochondrial genome as a source of bioactive signalling molecules. It is used as a tool compound in studies examining mitochondria-to-nucleus communication.
Metabolic disease models: MOTS-c’s AMPK-activating and insulin-sensitising properties have made it a subject of research in type 2 diabetes, obesity, and metabolic syndrome preclinical models.
Aging and longevity research: Circulating MOTS-c levels have been reported to decline with age in both murine and human cohorts. Research in C. elegans and murine aging models has examined MOTS-c’s role in extending healthspan via metabolic reprogramming and stress response activation.
Skeletal muscle research: MOTS-c’s role in skeletal muscle glucose metabolism, mitochondrial function, and exercise adaptation makes it a relevant tool compound in muscle cell biology and sarcopenia research.
Sourcing MOTS-c for Research
R&D Peptides supplies MOTS-c 20mg and 40mg as a lyophilised research compound with a batch-specific Certificate of Analysis. Supplied strictly for in vitro research use only.
For quality and testing standards, see our quality and testing page, or browse our full Longevity & Anti-Ageing research compound range.
All content on this page is for educational and informational purposes only. MOTS-c is supplied by R&D Peptides strictly for in vitro research use. It is not intended for human or veterinary administration, and no therapeutic claims are made or implied.
