Research digest / Mitochondrial-derived peptide
MOTS-c peptide is a mitochondrial-derived signalling molecule mapped across metabolic, neuroprotection, and aging research.
Sixteen amino acids. One founding 2015 paper. A reproducible AMPK mechanism. And a human evidence base that is observational, not interventional. Every figure on this site is laid out as a specimen and cited to its study.
The short version
MOTS-c peptide is a tiny protein your own mitochondria make. Mitochondria are the parts of a cell that turn food into usable energy, and MOTS-c is a 16-link chain written into their DNA. In mice, giving extra MOTS-c improved blood-sugar control, cut diet-driven fat gain, and boosted running capacity [1][2]. Exercise raises your own MOTS-c levels, which is why researchers call it an "exercise mimetic" — a molecule that copies some effects of a workout. The catch: no completed human trial has tested whether injecting MOTS-c does any of this in people. Everything below is from cells, animals, and human blood-sample studies.
What Is MOTS-c?
MOTS-c is a 16-amino-acid peptide, sequence MRWQEMGYIFYPRKLR, encoded by a short open reading frame inside the mitochondrial 12S ribosomal RNA gene (MT-RNR1) [4]. Its molecular weight is 2174.61 Da and its CAS number is 1627580-64-6. It belongs to a small class called mitochondrial-derived peptides (MDPs) — bioactive peptides written into mitochondrial DNA rather than the cell's nuclear DNA, alongside humanin and the SHLPs [4].
Unlike a synthetic research compound, MOTS-c is endogenous: it is detectable in human plasma and skeletal muscle, and circulating levels are exercise-inducible and shift with age and metabolic state [2][4]. That dual identity — a molecule the body already produces, now also studied as an injected agent in animals — frames everything on this site. The bare term MOTS-c and the fuller "MOTS-c peptide" both refer to this single mitochondrial-encoded molecule; this is not a blend.
What Does the MOTS-c Peptide Do?
MOTS-c is a 16-amino-acid peptide encoded within the mitochondrial 12S rRNA gene. It inhibits the folate cycle and de novo purine biosynthesis, raising AICAR and activating AMPK, which improves glucose handling and insulin sensitivity in skeletal muscle in animal models [1][4]. Under metabolic stress it also moves into the nucleus and helps regulate stress-response genes [3].
MOTS-c: A Mitochondrial-Derived Peptide
The founding 2015 paper in Cell Metabolism identified MOTS-c and its core mechanism: it inhibits the folate cycle (the set of reactions that move one-carbon units used to build purines), which raises AICAR (5-aminoimidazole-4-carboxamide ribonucleotide, a natural AMPK activator) and switches on AMPK — AMP-activated protein kinase, the enzyme a cell uses as its low-fuel sensor [1]. That study identified skeletal muscle as the primary target tissue and showed MOTS-c treatment prevented diet-induced obesity and insulin resistance in mice [1].
The biology widened from there. A 2018 study showed that under metabolic stress MOTS-c translocates from the mitochondrion to the nucleus and regulates nuclear gene expression — the first demonstrated retrograde signalling by a mitochondrial-encoded peptide [3]. A 2021 Nature Communications paper established that exercise induces endogenous MOTS-c and that exogenous MOTS-c enhanced physical performance across young, middle-aged, and old mice [2]. A 2024 study added a direct molecular target: casein kinase 2 (CK2), a constitutively active enzyme MOTS-c binds and modulates tissue-specifically [13].
The full mechanism, study by study, is set out on the MOTS-c benefits in studies page; the MOTS-c neuroprotection research page covers the brain and cognition work specifically.
Where the evidence is strong, and where it stops
Strong: the mechanism is reproducible. AMPK activation via folate-cycle inhibition has been shown in cells and animals by multiple groups, and the exercise-inducibility of endogenous MOTS-c is well documented [1][2][3]. The 2015 metabolic-homeostasis result and the 2021 exercise-capacity result are the two load-bearing animal findings.
Honest: there are no completed interventional human efficacy trials of exogenous MOTS-c. The human evidence is observational — circulating MOTS-c is decreased in obese children, altered by chronic endurance exercise in athletes, and independently associated with mortality and cardiovascular risk in hemodialysis patients [6][7][9]. Those are associations in people who were not given the peptide. Rodent doses of 0.5-15 mg/kg/day cannot be read across to humans, and no validated human half-life has been published [1][2]. See MOTS-c dosage in research for the dose record and frequently asked questions for the safety context.