What Is MOTS-c? Research Background and Study Areas

The MOTS-c peptide belongs to a small group of mitochondrial-derived peptides, short sequences whose coding information lies in mitochondrial DNA rather than in the nuclear genome. This profile sets out what the peptide is, which models have been used to study it, what the human literature contains and where the evidence stops. It closes with how a certificate confirms identity, the same questions covered in the page on how lots are analyzed before listing.

This profile covers published laboratory research only. Other compound profiles are collected in the Journal archive.

What the MOTS-c peptide is

The name stands for mitochondrial open reading frame of the 12S rRNA-c. Lee and colleagues reported it in Cell Metabolism in 2015 after an in silico search of the human 12S rRNA found a 51 base pair open reading frame that translates into a 16 amino acid peptide. The same paper describes the sequence as highly conserved across 14 species, especially the first 11 residues. At the time, the authors noted, humanin was the only other reported mitochondrial-derived peptide whose open reading frame mapped to mitochondrial DNA. The UniProt reference entry lists the human sequence as MRWQEMGYIFYPRKLR, 16 residues, with a calculated molecular weight of 2175 daltons, and assigns it to the MT-RNR1 gene.

To test whether the sequence was truly mitochondrial rather than a copy held in the nuclear genome, the 2015 authors depleted mitochondrial DNA in HeLa cells and reported loss of MOTS-c transcripts. They also noted that rats carry no nuclear copies of the sequence, which leaves mitochondrial DNA as its only source in that species. The Journal’s GHK-Cu research profile and Epitalon research profile follow the same format for two other compounds.

What published MOTS-c research examines

Most of the literature comes from cell culture and rodent work, and much of it from a small number of connected research groups. Each area below is labeled by study type.

• Cell metabolism, in vitro. In HEK293 cells, the 2015 study combined gene expression arrays with metabolomic profiling and reported that MOTS-c acted on folate metabolism and the linked de novo purine synthesis pathway, with accumulation of the intermediate AICAR and activation of AMPK, a cellular energy sensor.
• Nuclear signaling, in vitro. Kim and colleagues reported in 2018 that in cultured cells under metabolic stress, MOTS-c moved into the nucleus in an AMPK-dependent manner, was associated with changes in a broad set of nuclear genes, including those with antioxidant response elements, and interacted with the transcription factor NRF2.
• Metabolic measures, animal model. The 2015 paper also measured insulin sensitivity, glucose handling and body weight in mice fed a high-fat diet and in older mice. The authors described skeletal muscle as the apparent primary target tissue.
• Physical capacity and aging, animal model. Reynolds and colleagues reported in 2021 physical performance measures in young, middle-aged and old mice given MOTS-c, alongside skeletal muscle gene expression and the response of cultured myoblasts to metabolic stress.
• A sequence variant, animal model and in vitro. A 2021 study by Zempo and colleagues compared native MOTS-c with a K14Q variant in male and female mice on a high-fat diet and in insulin signaling assays in cells. The authors reported diminished activity for the variant in those assays.

These are model-system findings. They describe what happened in specific cell lines and mouse strains under specific conditions, and none of them is a measurement in people.

Human studies of MOTS-c so far

Published human work is small and observational, or genetic. As of September 21, 2026, we found no completed randomized trial of MOTS-c with posted results.

In the 2021 Reynolds study, 10 sedentary, healthy young men completed a single high-intensity cycling session, with skeletal muscle and plasma sampled around it. The authors reported that endogenous MOTS-c rose in muscle and in circulation with exercise. This was a small physiology study of the body’s own peptide, and no MOTS-c was given.

The Zempo study also included a meta-analysis of three cohorts totaling 27,527 people (J-MICC, MEC and TMM). It examined m.1382A>C, an Asian-specific mitochondrial DNA variant that changes the MOTS-c sequence at position 14. The authors reported an association between the C allele and a metabolic phenotype in men, but not in women. This is a genetic association study. It links a variant in the natural sequence to a population statistic and does not test the peptide itself.

What the research does not establish

The gaps are larger than the findings, and several are structural rather than a matter of waiting for more data.

• No human outcome data. No completed controlled trial of MOTS-c with published results was identified. FDA’s list of bulk drug substances that may present significant safety risks states that the agency has not identified any human exposure data on drug products containing MOTS-c and lacks important information on its safety. The same entry notes complexities with peptide-related impurities and characterization.
• Animal findings do not transfer. A result in a mouse strain on a controlled diet is a measurement in that model. It cannot be read as a measurement in people.
• Measurement is unsettled. A 2019 mass spectrometry study validated an LC/MS method for MOTS-c in plasma and could not confirm the endogenous levels a commercial ELISA reported in 20 healthy volunteers. The method also tracked four metabolites and two oxidation products. Circulating concentrations reported by immunoassay should be read with that discrepancy in mind.
• Concentrated authorship. Much of the core literature comes from connected groups, and authors of the 2018 and 2021 papers disclosed consulting or shareholder ties to CohBar, Inc.
• Mechanism is incomplete. The 2021 Reynolds authors describe the detailed molecular mechanism as an active field of research, and the pathways reported so far come largely from cell models.

Reading a MOTS-c certificate of analysis

For a laboratory, the practical questions are identity and traceability. A certificate should show that the material in a specific lot is the 16 residue sequence described above, analyzed by a named laboratory on a stated date. Mass spectrometry is the identity test: the observed mass should match the value calculated for MRWQEMGYIFYPRKLR, allowing for the ion form reported. The sequence contains two methionine residues, which is why oxidation products appear among the targets of published LC/MS methods, and a chromatogram showing related peaks says more than a single summary figure.

• Lot number on the certificate matches the vial label
• Sequence stated as MRWQEMGYIFYPRKLR, 16 residues
• Identity confirmed by mass spectrometry, with observed and expected mass shown
• HPLC chromatogram included, not only a summary figure
• Testing laboratory named and test date stated
• Salt or counterion form stated where applicable

Goated Peptides publishes lot records in the lot-matched certificate library. The terms that govern research use are set out in the research use only policy and the compliance overview, and common documentation questions are answered in the documentation FAQ. To see how these fields appear in practice, look up a published MOTS-c lot record in the certificate library and compare it line by line with the checklist above.

Frequently asked questions